i.ft-Vtt wi TV* 1 1-7 1 d Pify N \Y : ' / THE ANIMAL KINGDOM ARRANGED IN CONFORMITY WITH ITS ORGANIZATION, BY THE BARON CUVIER, PERPETUAL SECRETARY TO THE ROYAL. ACADEMY OF SCIENCES, ETC. ETC. ETC. THE CRUSTACEA, ARACHNIDES AND INSECTA, BY P. A. LATREILLE, MEMBER OF THE ROYAL, ACADEMY OF SCIENCES, ETC. ETC ETC. TRANSLATED FROM THE FRENCH WITH NOTES AND ADDITIONS, BY H. M'MURTRIE, M.D. &c. &c. IN FOUR VOLUMES, WITH PLATES VOLUME III. NEW YORK : G. & C.& H. CARVILL. MDCCCXXXI. Entered according to the act of congress, in the year one thousand eight hundred and thirty-one, by G. & C. & H. Carvill, in the clerk's office of the southern district of New York. Philadelphia : Printed by James Kay, Jun. & Co. Piinters to the American Philosophical Society. No. 4, Minor Street. PREFACE(l). Overwhelmed with scientific labours, and yielding, perhaps too easily, to the impulse of friendship and to my desire to serve him, M. Cuvier has confided to me that portion of this work which treats of Insects. These animals were the objects of his earliest zoological studies, and the cause of his connexion with one of the most celebrated pupils of Linnaeus, Fabricius, who in his writings gives him frequent assurance of his high esteem. It was even by various interesting observations on several of these ani- (1) This preface is the same which stood at the commencement of the third volume of the first edition of this work. Having there confined myself to an ex- position of the general principles, upon which my arrangement of the animals composing the Linnrean class of Insects was effected, and having in the present edition made no change in that respect, the same observations are still applicable. Considered however with regard to the details, or to the secondary and tertiary divisions, that is to say, Orders, Families, Genera and Subgenera, this edition will be found to present a remarkable difference. It was impossible to place it on a level with the actual state of the science, without modifying several parts of my former system, and without considerable additions, which, such has been the pro- gress of Entomology, are so numerous, that even by filling two volumes instead of one, I have been barely enabled to give a very summary view of the multitude of generic divisions effectuated within the last ten years, and which are frequently founded on the most minute characters. This branch of Zoology has gained much from other and more positive sources, those of Anatomy. These observations I was the more imperatively bound to notice, as they formed part of the plan of the illustrious author of the "llegne Animal," and as they serve to confirm the stability of the divisions I have established. By a perusal of the general remarks which precede them, the reader will be better able to appreciate the motives which have determined these changes, and to feel the importance of the addenda that enrich the entomological portion of this edition. A simple comparison between it and that of the former will show, at a glance, that it has been entirely remoulded, or that it is a new work which we now present to the world, rather than a new edition. IV PREFACE. mals Journal iVHist. Nat. that M. Cuvier commenced his career in natural history. Entomology, in common with all the other branches of Zoology, has derived the greatest advan- tage from his anatomical researches, and the happy changes he has effected in the basis of our classification. The internal or- ganization of Insects is now better known, and this study is no longer neglected as was previously the case. He has placed us on the way to the Natural System(l), and greatly will the public regret that his numerous occupations did not allow him to superintend this portion of his treatise on animals. Perhaps the desire of associating my name with his in a work like this, which, by the multitude of researches on which it rests, and by their application, has become a precious literary monument of the age, has deceived me and thrown me into an enterprize beyond my powers to accomplish. The responsibility is great, and I have imposed upon myself a task, in which the boldness of the plan is only equalled by the dif- ficulty of its execution. To unite within a very limited space the most interesting facts in the history of Insects, to arrange them with precision and clearness in a natural series, to pour- tray with a bold pencil the physiognomy of these animals, trace their distinguishing characters with truth and brevity, in a way proportioned to the successive progress of the science and that of the pupil, to indicate useful or noxious species, and those whose mode of life interests our curiosity, to point out the best sources from which the knowledge of others may be obtained, to restore to Entomology the amiable simplicity which it possessed in the days of Linnaeus, Geoffroy, and of the early writings of Fabricius, but still to present it as it now is, or with all the wealth of observation it has since acquired, yet without overloading it ; in a word, to conform to the mo- del before me, the work of M. Cuvier, is the end I have striven to attain. This savant, in his " Tableau Elementaire de FHistoire Na- turelle des Animaux," did not restrict the extent given by (1) Tableau Element, de 1'IIist. Nat. des Animaus, and the Leg. d'Anat. Compar. 1'ltUFACE. V Linnaeus to his class of Insects ; he however made some necess- ary ameliorations, which have since served as the foundation of other systems. He distinguishes Insects, in the first place, from other invertebrate animals, by much more rigorous cha- racters than those previously employed, viz. a knotted medul- lary spinal marrow, and articulated limbs. Linnaius termi- nates his class of Insects with those which are apterous, although most of them, such as the Crustacea and the Jlra- neides, with respect to their organization, are the most per- fect of their class or are the most closely approximated to the Mollusca. His method, in this respect, is then exactly the inverse of the natural system, and by transporting the Crus- tacea to the head of the class, and by placing almost all the Aptera of Linnaeus directly after them, Cuvier rectified the method in a point where the series was in direct opposition to the scale formed by Nature. In his Legons d' Anatomic Comparce, the class of Insects, from which he now separates the Crustacea, is divided into nine orders, founded on the nature and functions of the or- gans of manducation, the presence or absence of wings, their number, consistence, and the manner in which they are reti- culated. It is in fact a union of the system of Fabricius with that of Linnseus perfected. The divisions made by our savant in his first order, that of the Gnathaptera, are nearly similar to those I had established in a Memoir presented to the Societe Philomatique, April 1795, and in my Precis des Carac teres Gmeriques des In- sect es{\). M. de Lamarck, whose name is so dear to the friends of natural science, has ably profited by these various labours. His systematic arrangement of the Linnsean Aptera appears to us to be that which approaches nearest to the natural order, and, with some modifications of which we are about to speak, is the one we have followed. (1) 1 there divided the Aptera of Linnceus into seven orders: 1. The Suctoiua. 2. The Thi8anouiu. 3. The Takasita. 4. The Acephala (Arac/mldca pal- pistes,Lm\.)- 5. The Entomosthaca 6. The Crustacea. 7 The Miiuajoda. VI PREFACE. I divide the Insects of Linnaeus, with him, into three classes : the Crustacea, Arachnides and Insecta; but in the essential characters which I assign to them, I abstract all the changes experienced by these animals, prior to their adult state. This consideration, although natural, and previously employed by De Geer in his arrangement of the Aptera, is not classical, inasmuch as it supposes the observation of the animal in its different ages ; it is, besides, liable to many ex- ceptions^). The situation and form of the branchiae, the manner in which the head is united to the thorax, and the organs of man- ducation, have furnished me the means of establishing seven orders in the class of the Crustacea, all of which appear to me to be natural. I terminate it, with M. de Lamarck, by the Branchiopoda, which are a sort of Crustacea Jlrachnides. In the following class, that of the Arachnides, I only in- clude the species which in the system of Lamarck, compose the order of his Arachnides paipistes, or those which have no antennae. Beyond this, the organization of these animals, external as well as internal, furnishes us with a simple and rigorous rule that is susceptible of a general application. Their organs of respiration are always internal, receiving air through concentrated stigmata, sometimes possessing func- tions analogous to those of lungs, and consisting at others of radiated tracheae, or such as ramify from their base; the an- tennae are wanting, and they are usually furnished with eight feet. I divide this class into two orders: the Pulmonarise and the Trachearise. Two parallel tracheae, extending longitudinally through the body, furnished at intervals with centres of branches corres- (1) These considerations, however, have not been overlooked, and I have used them advantageously in grouping families, and arranging them in a natural order, as may be seen by a reference to the historical sketches which precede the expo- sition of those families. I have even been employed on a work respecting the metamorphosis of Insects in general, which has not yet been published (see article " Insectcs" Nouv. Diet. d'Hist. Nat. Ed. 2d), but which I have long been matur- ing, and which I have communicated to my friends: I have made use of it in the course of my general remarks. PREFACE. Vll ponding to the stigmata, and two antennae, characterize the class of Insects. Its primary divisions are founded on the three following considerations : 1 . Jlpterous Insects which either undergo no metamorpho- ses, or but imperfect ones ; the three first orders. 2. Jlpterous Insects which experience complete transfor- mations ; the fourth. 3. Insects having wings which they acquire by metamor- phoses, either complete or incomplete ; the last eight. I begin with the Jlrachnides antennistes of M. de Lamarck, which are comprised in this first division, and which form our three first orders. The second is composed of the fourth order, and contains but a single genus, that of Pulex : it would appear, in some respects, to be allied to the Diptera by means of the Hippoboscse ; other characters however, and the na- ture of its metamorphoses, remove this genus from that of the Hippoboscce. It is very difficult in some cases to distinguish these natural filiations, and when we are fortunate enough to discover them, we are frequently compelled to sacrifice them to the perspicuity and facility of the system. To the known order of winged Insects, I have added that of the Slresiptera of Kirby, but under a new denomination, . viz. that of flhipiptera, as the former appears to me to be founded on a false idea. Perhaps we should even suppress this order, according to the opinion of Lamarck, and unite it with that of the Diptera. For reasons elsewhere developed(l), and which I could easily strengthen by additional proof, I attach more conse- quence to characters drawn from the aerial locomotive organs of Insects, and to the general composition of their body, than to the modifications of the parts of the mouth, at least when their structure is essentially referable to the same type. Thus I do not commence by dividing these animals into Grinders and Suckers, but into those which have wings and wing-cases, and such as have four or two wings of the same consistence. The form and uses of the organs of manducation are viewed (1) Consid. Gener. sur I'ordre des Crust., des Arach., et des Insectes, p. 46. Vlll PREFACE. in a secondary light. My series of Orders relative to the winged Insects is, consequently, nearly similar to that of Linnseus. Fabricius, Cuvier, Lamarck, Clairville and Dumeril, con- sidering the difference of the functions of the parts of the mouth of primary consequence, have arranged those divisions otherwise. In accordance with the plan of M. Cuvier, I have reduced the number of families which I established in my previous works, and have converted into subgenera the numerous divi- sions that have been made of the genera of Linnseus, notwith- standing their characters may otherwise be very distinct. Such also was the intention of Gmelin in his edition of the Systerna Naturse. This method is simple, historical and convenient, as it enables the student to proportion his instruc- tion to his age, his capacity, or to the end he has in view. . All my groups are founded on a comparative examination of all the parts of the animals I wish to describe, and on the observation of their habits. Most Naturalists stray from the natural system by being too exclusive in their considerations. To the facts collected by Reaumur, Rcesel, De Geer, Bonnet, the Hubers, &c. respecting the instinct of Insects, I have added several ascertained by myself, some of which were hitherto unknown. M. Cuvier has added to them an extract of his anatomical observations(l); he has even devoted himself to fresh researches, among which I will mention those whose object was the organization of the Limuli, a very singular genus of the Crustacea. Being necessarily restricted in the description of species, I have always selected for that purpose the most interesting and common ones, and particularly those mentioned by M. Cuvier in his Tableau Elementaire de PHistoire Naturelle des Animaux. LATREILLE. (1) Those added to the present edition are from Messrs Leon Dufour, Marcel de Serres, Straus, Audouin and Milne Edwards. SYSTEMATIC INDEX. ARTICULATA with arti- culated FEET. CLASS I. CRUSTACEA Their division into orders MALACOSTRACA a. Eyes placed on a mova- ble and articulated pe- dicle DECAPODA BRACHYURA Cancer Pinnipedes Matuta Polybius Orythyia Podopthalmus Portunus Platyonichus Arcuata Cancer proper Clorodius Carpilius Xantho{\) Pirimela Atelecyclus Thia Mursia Hepatus Quadrilatera Eriphia Trapezia Pilumnus Thelphusa Gonoplax Maci'opthalmus Gelasimus Ocypode Mictyris 1 6 9 12 12 13 20 21 21 22 22 23 23 24 25 26 26 27 27 27 27 27 28 28 29 29 30 30 30 30 32 32 33 34 35 Pinnotheres 35 Uca 36 Cardisoma 37 Gecarcinus 37 Plagusia 38 Grapsus 38 Orbiculata 39 Corystes 39 Leucosia 39 Ixa 40 Iphis 40 Nursia 40 Jircania 40 Ilia 40 Persephona 40 Myra 40 Leucosia 40 Phylira 40 Eb'alia 41 Trigona 41 Parthenope 42 Lambrus 42 Mithrax 43 Acanthonyx 43 Pisa 43 Pericera 43 Maia 44 Micippe 44 Stenocionops 44 Camposcia 45 Halimus 45 Hyas 45 Libinia 46 Doclxa 46 Egeria 46 Leptopus 47 Hymenosoma 47 Inachus 48 Achaeus 48 Stenorhynchus 48 Leptopodia 48 (1) Those genera which we mention accessorily, either because they are but slightly or not at all known to us, or because we unite them with others, are printed in italics. Vol. III. (2) SYSTEMATIC INDEX. Pactolus 49 Lithodes 49 Cryptopoda 49 Calappa 49 jEthra 49 Notopoda 51 Homola 51 Dorippe 51 Dromia 52 Dynomene 52 Rairina 52 MACROURA 54 Astacus 55 Anomala 55 Albunea 56 Hippa 56 Remipes 57 Birg-us 58 Pagurus 58 Cxnoblta 58 Pagurus 59 Prophylax 59 Locuslae 60 Scyllarus 60 Thenus 61 Ibacus 61 Palinurus 61 Astacini 62 Galathea 63 Grimotea 63 Muni da 63 JEglea 64 Janira 64 Porcellana 64 Monolepis 65 Megalopus 65 Gebia 66 Thalassina 66 Callianassa 66 Axius 67 Eryon 67 Astacus proper 67 Nephrops 68 Carides 69 Penseus 70 Stenopus 71 Atya 71 Crangon 71 Processa 73 Hymenocera 73 Gnathophyllum 73 Pontonia 73 Alpheus 73 Hyppolite 74 Autonomera 74 Pandalus 74 Palscmon 74 Lysmata 75 Athanas 75 Pasiphxa 76 Mysis 76 Cryptopus 77 Mulcion 77 STOMAPODA 77 UNIPELTATA 81 Squilla 82 Squilla proper 82 Gonodactylus 83 Coronis 83 Erichthus 83 Alima 84 BIPELTATA 84 Phyllosoma 84 (3. Eyes sessile and immoi )- able 85 AMPHIPODA 87 Gammarus 87 Phronima 88 Hyperia 88 Phrosine 89 Dactylocera 89 lone 90 Orchestia 91 Taliprus 91 Atylus 91 Gammarus proper 92 Melita 92 Mxra 92 Amphithoe 92 Pherusa 92 Dexamine 93 Lencothoe 93 Cerapus 93 Podocerus 93 Jassa 93 Corophium 94 Pterygocera 94 Apseudes 95 Typhis 95 Anceus 95 Praniza 96 Ergine 96 LJLMODIPODA 96 Cyamus 97 Leptomera 97 Naupredia 98 Caprella 98 Cyamus proper 98 ISOPODA * 99 Oniscus 100 Bopyrus 101 Serolis 101 Cymothoa 102 Ichthyophilus 102 Nerocila 102 Livoneca 102 Canolira 102 JEga. 103 Rocinela 103 Conilira 103 Synodus 103 SYSTEMATIC INDEX. XI Nelocira 103 Eurydice 103 Limnoria 104 Zuzara 105 Sphaeroma 105 Nsesa 105 Campecopea 105 Cilicxa 105 Cymodocea 106 Dynamene 106 A nth ara 106 Idotaea 106 Stenosoma 107 Arcturus 107 Asellus 107 Oniscoda 108 J sera 108 Tylos 108 Ligia 109 Philoscia 109 Oniscns proper no Porcellio 110 Armadillo 110 ENTOMOSTRACA 112 BRANCHIOPODA 114 Monoculus 115 Lophyropa 115 Zoea 117 NSbalia 117 Condylura 118 Cyclops 119 Cythere 122 Cypris 122 Sida 125 Latona 125 Polyphemus 126 Daphnia 127 Lynceus 132 Phyllopa 132 Lirnnadia loo Artemia 134 Branchipus 134 Eulimene 137 Apus 138 Lepidurus 141 P.E.CILOPODA 141 XYPHOSURA 142 Limulus 142 Tachypleus 145 SIPHONOSTOMA 146 CALLIG1DES 146 Argulus 147 Caligus 150 Caligus proper 151 Pterygopoda 151 Pandarus 151 Dinemoura 151 Anthosoma 152 Cecrops 152 LERNEIFORMES 152 Dichelestium 153 Nicothoe 154 TRILOBITES 155 Agnostus 157 Calymene 157 Asaphus 157 Ogygia 157 Paradoxides 157 CLASS II. ARACHNIDES 159 PULMONARY 162 ARANEIDES 164 Mygale 173 Mygale proper 174 Ctcniza 175 Atypus 177 Eriodon 178 Dysdera 179 Filistata 179 Aranea 179 Tubitelae 180 Clotho 180 Drassus 182 Segestria 183 Clubiona 183 Aranea proper 184 Argyroneta 184 Inequkelae 184 Scytodes 185 Theridion 185 Episinus 186 Pholcus 186 Orbitelae 186 Linyphia 187 Uloborus 187 Tetragnatha 188 Epeira 188 Laterigradae 191 Micrommata 191 Senelops 192 Philodromus 193 Thomisus 194 Storena 195 Citigradse 196 Oxyopes 196 Ctenus 196 Dolomedes 197 Lycosa 197 Myrmecia 199 PEDIPALPI 202 Tarantula 202 Phrynus 202 Thelyphonus 203 Scorpio 203 TRACHEARI^ 206 PSEUDO-SCORPIONES 207 Galeodes 208 Chelifer 209 Xll SYSTEMATIC INDEX. PYCNOGONIDES 210 Pediculus proper Pycnogonum 211 Hsematopinus Phoxichilus 211 Ricinus Trichodedes Nymphon Jimmothea 211 211 Gyropiis Zdotheum HOLETRA 212 Philupterus Phalangita 212 Goniodes Phalangium 213 Triongulin Gonoleptes 213 SUCTORIA Siro 214 Pulex Macrocheles 214 COLEOPTERA Trogulus 214 Pentamera. ACABIDES 214 CARNIVORA Acarus 214 TRIBE I. Trombidium 215 ClCINDELETJE Erythrxus 215 Cicindela Gamasus 215 Manticora Cheyletus Oribata Uropoda Acarus proper Bdella Smaridia Ixodes 216 216 216 217 217 217 218 Megacephala Oxycheila Euprosopus Cicindela proper Ctenostoma Therates Colliuris Argas Eylais 219 219 Tricondyla Hydrachna 219 TRIBE II. Limnochares 220 Carabici Caris 220 Carabus Leptus 220 Truncatipennes Aclysia 220 Anthia Atoma 221 Graphipterus Ocypete 221 Aptinus CLASS III. Brachinus INSECTA 229 Corsyra Casnonia MYRIOPODA 245 Leptotrachelus CHLLOGNATHA 247 Odacantha lulus 249 Zuphium Glomeris 250 Polistichus lulus proper 250 Helluo Polydesmus 251 Drypta Pollyxenus 251 Trichognatha CHILOPODA 251 Galerita Scolopendra Scutigera 251 253 Cordistes Ctenodactyla Agra Lithobius 253 Scolopendra proper 254 Cymindis Calleida Demetrias THYSANOURA 255 LEPI9MENJE 255 Dromias Lepisma 255 Lebia Machilis 256 Plochionus Lepisma proper 256 Orthogonius PODURELLiE 256 Coptodera Podura 257 Bipartiti Podura proper 257 Enceladus Smynthurus 257 Siagona PARASITA 258 Carenum Pediculus 258 Pasimachus 258 260 260 261 261 261 261 262 262 262 263 264 266 269 269 269 270 270 270 270 272 272 273 273 273 274 274 275 275 276 276 277 278 278 278 279 279 279 280 281 281 281 282 282 282 283 283 283 283 284 284 284 284 285 285 286 287 SYSTEMATIC INDEX. Xlll Acanthoscelis 287 Scarites 288 Oxygnathus 289 Oxystomus 289 Camptodontus 289 Clivina 290 Dischirius 290 Morio 290 Ozaena 290 Ditomus 291 Aristus 291 Apotomus 291 Quadrimani 291 Acinopus 292 Daptus 293 Harpalus 293 Ophonus 294 Stenolophus 294 Acupalpus 294 Simplicimani 294 Zabrus 296 Pogonus 296 Tetragonoderus 297 Feronia 297 Amara 297 Psecilus 297 Argutor 297 Omaseus 297 Flatysma 297 Pterostichus 297 Abax 297 Steropus 297 Percus 297 Molops 297 Cophosus 297 Cheporus 299 My as 300 Trigonomota 300 Pseudo-morpha 300 Cephalotes 301 Stomis 301 Catascopus 301 Colpodes 301 Pericalus 301 Mormolyce 302 Sphodrus 302 Ctenipus 303 Calathus 303 Taphria 303 Patellimani 303 Dolichus 304 Platynus 304 Agonum 304 Anchomenus 305 Callistus 305 Oodes 305 Chlxnius 305 Epomis 306 Dinodes 306 Lissauchenus 306 Rembus 306 Dicxlus 307 Licinus Badister Pelecium Cynthia Panagseus Loricera Patrobus Grandipalpi Pamborus Cychrus Scaphinotus Sphseroderus Tefflus Procerus Procrustes Carabus proper Pkctes Cechenus Calosoma Pogonophorus Nebria Alpasus Omophron Elaphrus Blethisa Pelophilus Notiophilus Subulipalpi Bembidium Tachypus Lopha Notaphus Peryphus Leja Trechus Blemus tribe iii. Htdbocanthahi Dytiscus Dytiscus proper Colymbetes Hygrobia Hydroporus Noterus Haliplus Gyrinus B11ACHELYTRA Staphylinus Fissilabra Oxyporus Astrapsus 307 307 308 308 308 309 309 310 310 310 311 311 311 311 312 312 312 312 313 315 315 315 316 316 316 316 317 317 318 318 318 318 318 318 319 319 319 320 321 323 324 324 325 325 325 327 327 328 329 329 Staphylinus proper 329 JCantholinus 330 Pinophilus 330 Lathrobium 330 Longipalpi 331 Psederus 331 Procirrus 331 Stilicus 331 Evsesthetus 331 Stenus 332 XIV SYSTEMATIC INDEX. Denticrura Oxytelus Osorius Zyrophorus Prognatha Coprophilus Depressa Omalium Lesteva Micropeplus Proteinus Aleochara Microcephala Lomechusa Tachinus Tachyporus SERRTCORNES section i. Sternoxi TRIBE I. BUPRESTIDES Buprestis Buprestis proper Trachys Aphanisticus Melasis THIBE II. Elaterides Elater Galba Eucnemis Adelocera Lissomus Chelonarium Throscus Cerophytum Cryptostoma Nematodes Hcmirhipus Ctenicera Elater proper Campylus Phyllocerus section ii. Malacodehjii TKIBE I. Cebbio>'ites Cebrio Physodactylus Cebrio proper Anelastes Callirhips Sandalus Rhipicera Ptilodactyla Dascillus Elodes Scyrtes Nycteus Eubria 332 332 332 333 333 333 333 333 333 334 334 334 334 o r> - 335 335 338 339 340 340 340 340 342 342 342 342 343 343 344 344 344 345 345 345 346 346 347 347 347 348 348 349 349 349 350 350 350 350 351 351 351 THIBE II. Lampthides 351 Lampyris 352 Lycus 352 Dictyoptera 352 Omalisus 353 Amydttts 354 Pbengodes 355 Lampyris proper 355 Drilus 356 Cochleodonus 356 Telephorus 357 Silis 358 Malthinus 358 THIBE III. Meeyrides 358 Melyris 359 Malachius 359 Dasytes 360 Zygia 360 Melyris 360 Pelocophorus 361 Diglobicei'us 361 THIBE IV. Ceehii 361 Clerus 361 Cylidrus 361 Tillus 362 Priocera 362 Axina 362 Eurypus 362 Thanasimus 363 Opilo 363 Clerus proper 363 Necrobia 364 Enoplium 364 THIBE v. Ptijtiohes 364 Ptinus 365 Ptinus proper 365 Gibbium 366 Ptilinus 366 Xyletinus 367 Dorcatoma 367 Anobium 367 SECTION III. THIBE I. Xylothogi 368 Lymexylon 368 Atractocerus 368 Hylecjetus 369 Lymexylon propel 369 Cupes 369 Rhysodes 370 CLAVICOHNES 370 SECTION I. THIBE I. Paepatohes 371 Mastigus 371 Mastigus 371 Scydm?enus 371 SYSTEMATIC INDEX. XV TRIBE II. HlSTEROIDES Hister Hololepta Hister proper Platysoina Dendrophilus Abrxus Onthophilus TRIBE III. SlLPHALES Silpha Sphxrites Necrophorus Necrodes Silpha proper Thanatophilus Oiceptoma Phosphuga Necrophilus Argyrtes TRIBE IV. SCAPHIDITES Scaphidium Scaphidium proper Choleva tribe v. NlTIDTTXARiaj Nitidula . Colobicus Thymalus Ips Nitidula proper Ceixus Byturus TRIBE VI. ExGIDITES Dacne Dacne proper Cryptophagus tribe vii. Dermestini Dermestes Aspidiphorus Dermestes proper Megatoma Limnichus Attagenus Trogoderma Anthrenus Globicornis tribe VIII. Bxrrhii Byrrhus Nosodendron Byrrhus proper Trinodes section ii. tribe i. AcANTHOPODA Heterocerus 372 O I O o7o 374 374 374 374 374 375 375 375 376 377 378 578 379 379 379 380 380 380 380 381 381 381 382 382 382 383 383 383 384 384 384 385 385 385 385 386 386 387 387 387 387 388 388 388 388 389 390 390 TRIBE II. Macrodacttla 390 Dryops 391 Potamophilus 391 Dryops proper 391 Elmis 392 Macronychus 392 Georissus 392 PALPICORNES 392 TRIBE I. Hydhophii.ii 393 Hydrophilus 393 Elophorus 394 Hydrochus 394 Ochthebius 394 Hydracna 393 Spercheus 394 Globaria 395 Hydrophilus proper 396 Limnebius 397 Hydrobius 397 Berosus 397 TRIBE II. Sph\bridiota Sphaeridium Cercydion LAMELLICOllNES TRIBE I. SCARABJEIDES Scarabaeus Coprophagi Ateuchus Pachysoma Gymnopleurus Sisyphus Circellium Coprobius Chseridium Hyboma Eurysternus Oniticellus Onthophagus Onitis Phanjeus Copris Aphodius Psammodius Euparia Arenicoli ^gialia Chiron Lethrus Geotrupes Ochodscus Athyreus Elephastomus Bolbocerus Hybosorus Acanthocerus Trox Phoberus 398 398 398 399 401 401 402 403 404 404 405 405 405 405 405 405 406 406 407 407 407 408 408 408 409 409 409 410 411 412 412 412 413 413 414 414 414 XVI SYSTEMATIC INDEX. Cryptodus 414 Msechidius 414 Xylophili 415 Oryctes 413 Agacephala 416 Orphnus 416 Scarabxus proper 417 Phileurus 417 Hexodon 418 Cyclocephala 418 Chrysophora 419 Rutela 419 Macraspis 419 Chasmodia 419 Ometis 420 Phyllophagi 420 Pachypus 421 Ambly teres 421 Anoplognathus 422 Leucothyreus 422 Apogonia 422 Geniates 422 Melolontha proper 423 Rhisotrogus Amphimalla Ceraspis Arcodes Dasypus S erica Diphucephala Macrodactylus Plectris Popilia Euchlora Mimela Anisoplia Lepisia Dicrania Hoplia Monocheles Anthobii Glapbyrus Amphicoma Anthipna Chasmopterus Chasme Dicheles Lepitrix Pachycnemus Anisonyx Melitophili Trichius Platygenia Cremastocheilus Goliath Inca Cetonia Gymnetis Macronota TRIBE II. LtJCANIDES Lucanus 425 425 425 426 426 426 426 427 427 427 427 427 427 427 428 428 428 429 429 430 430 430 431 431 431 431 431 432 433 434 434 435 435 435 436 436 437 437 Sinodendron JEsalus Lamprima Ryssonotus Pholidotus Lucanus proper Ceruchus Platycerus Nigidius .?Egus Figulus Syndesus Passalus Paxillus Heteromera. MELASOMA Pimelia Pimeila proper Trachyderma Cryptucheile Erodius Zophosis Nyctelia Hegeter Tentyria Akis Elenophorus Eurycliora Adelostoma Tagenia Psammetichus Scaurus Scotobius Sepidium Trachynotus Moluris Blaps Oxura Acanthomera Misolampus Blaps proper Gonopus Heteroscelis Machla Scotinus A si da Pedinus Opatrinus Dendarus Heliophilut Eurynotus Isocerus Pedinus, Dej. Blaptinus Platyscelis Tencbrio Cryptichus Opatrum Corticus Orthocerus Chiroscelis Toxium 438 438 438 439 439 439 440 440 440 440 440 440 441 441 442 444 445 446 446 446 446 447 447 447 448 448 449 449 450 450 450 450 450 451 451 452 453 453 453 453 454 454 455 455 455 456 456 456 456 456 456 457 357 457 458 458 458 459 459 459 459 SYSTEMATIC INDEX. XV11 Toxicum 459 Boros 460 Calcar 460 Upis 465 Tenebrio proper 460 Heterotarsus 461 TAXICOUNES 461 TRIBE I. DlAPERIALES 462 Diaperis 462 Phaleria 463 Diaperis proper 463 JSFeomida 463 Hypophlaus 464 Trachyscelis 464 Leiodes 464 Tetratom'a 464 Eledona 465 Coxelus 465 TRIBE II. CoSSYPHENES 465 Cossyphus 465 Cossyphus proper 466 Helseus 466 Nilio 466 STENELYTRA 466 TRIBE I. Heloph 468 Helops 468 Epitragus 469 Cnodalon 469 Campsia 469 Spheniscus 469 Camaria 469 Acanthopus 470 Amarygmus 470 Sphacrotus 470 Adelium 470 Helops proper 471 Lxna 471 Stenotrachelus 471 Strongylium 472 Pytho 472 Pelmatopus or ra- ther Scotodes 472 TRIBE II. ClSTEUDES 472 Cistela 472 Lystronichus 473 Cistela proper 473 Mycetochares 473 Allecula 474 TRIBE III. Serropalpides 474 Dircaea 474 Orchesia 474 Eustrophus 475 Hallomenus 475 Dircsea proper 475 Melandrya 475 Hypulus 476 Serropalpus 476 Vol. III. (3) Conopalpus 476 TRIBE IT. CEdemerites 477 CEdemera 477 Nothus 477 Calopus 478 Sparedrus 478 Dytillus 478 CEdemera proper 478 tribe v. Rhynchostoma 478 Mycterus 479 Stenostoma 479 Mycterus proper 479 Rhinosimus 480 TRACHELIDES 480 TRIBE I. Lagriari^; 480 Lagria 481 Lagria proper 481 Statyra 481 Hemipeplus 481 TRIBE II. Pyrocuroides 482 Pyrochroa 482 Dendroides 482 Pyrochroa 482 tribe iii. Mordellou^ 482 Mordella 483 Ripiphorus 483 Myodites 484 Pelocotoma 484 Mordella proper 484 Anaspis 485 Ctenopus 485 TRIBE IT. Anthicides 485 Notoxus 485 Scraptia 485 Steropes 486 Notoxus proper 486 TRIBE T. horiales 486 Horia 487 Horia proper 487 Cissites 487 TRIBE VI. Cantharidi.b 487 Meloe 487 Cerocoma 488 Hycleus 489 Mylabris 489 Lydus 489 CEnas 490 Meloe proper 491 Tetraonyx 492 Cantharis 492 Zonitis 493 Nomognathus 493 Gnathium 493 Will SYSTEMATIC INDEX. Sitaris 493 Onyctenus 493 Apalus 493 Tetramera. HHYNCOPHORA 494 Bruchus 496 Anthribus 496 Rhimaria 496 Bruchus proper 496 Rhosbus 497 Xylophilus 497 Attelabus 497 Apoderus 497 Attelabus proper 497 Rhynchites 497 Apion 497 Rhinotia 498 Eurhinus 498 Tubicenus 498 Brentus 498 Brentus proper 498 Ulocerus 499 Cylas 499 Brachycerus 499 Curculio 500 Cyclomus 500 Curculio proper 501 Leptosomus 502 Prostomus 502 Leptocerus 502 Cratopus 502 Lepropus 502 Hadromerus 502 Hybsonotus 502 Othiorhynchus 503 Omias 503 Pachyrhynchus 503 Psalidium 503 Thylacites 503 Syzygops 503 Hyphantus 503 Myniops 503 Liparus 503 Hypera 503 Hylobius 504 Cleonus 504 Lixus 504 Rhynchaenus 504 Tamnophilus 505 Bagous 505 Brachypus 5C5 Balanitis 505 Rhynchjenus proper 505 Sybines 505 Myorhinus 506 Cionus 506 Orchestes 506 Rhamphus 506 Amerhinus 507 Baridius 507 Camptorhynchus 507 Centrinus 507 Zyg-ops 507 Centrorhynchus 508 Hydaticus i08 Oribitis 508 Cryptorhynchus 508 Tylode 508 Calandra 509 Anclionus 509 Orthochaetes 509 Rhina 509 Calandra proper 509 Cossonus 510 Dryopthorus 510 XYLOPHAGI 510 Scolytus 511 Hylurgus 511 Hylesinus 511 Scolytus proper 511 Camptocerus 512 Ploiotribus 512 Tomicus 512 Platypus 512 Paussus 513 Pauasus proper 513 Cerapterus 513 Bos trie h us 514 Bostrichus proper 514 Psoa 514 Cis 514 Nemosoma 514 Monotonia 515 Synchita 515 Cerylon 515 Rhyzophagus 515 Monotoma proper 516 Lyctus 516 Lyctus proper 516 Diodesma 516 Bitoma 516 Mycetophagus 517 Colydium 517 Mycetophagus pro - per 517 Triphyllus 517 Meryx 518 Dasycerus 518 Latridius 518 Silvanus 518 Trogosita 518 Trogosita proper 519 Prostomis 519 Passandra 519 PLATYSOMA 519 Cucujus 520 Cucujus proper 520 Dendrophagus 520 Uleoiota 520 LONGICORNES 520 THTBE I. Priomi 522 SYSTEMATIC INDEX. Xl\ Parandra 523 Spondylis 523 Prionus 524 TRIBE II. Cerambicini. 525 Cerambyx 526 Lissonotus 526 Megaderus 527 Dorcacerus 527 Trachyderes 527 Loplionocerus 527 Ctenodes 528 Phaenicocerus 528 Callichroma 528 Acanthoptera 529 Stenocorus 529 Furpuriceiius 529 Cerambyx proper 530 Hamaticerus 530 Gnoma, Dej. 531 Callidium 532 Certalium 532 Clitus 532 Obrium 533 Rhinotragus 533 Necydalis 533 Stenopterus 533 Necydalis proper 534 Distichocera 534 Tmesisternus 535 Tragocerus 535 Leptocera 535 thibe iii. Lamiari.e 536 Acrocinus 536 Lamia 536 Acanthocinus 536 Tapeina 536 Pogonocherus 537 Tetraopes 537 Monochamus 537 Mesosa 537 Lamia proper 537 Dorcadion 538 Parmena 538 Saperda 538 Gnoma, Fab. 538 Adesmus 539 Apomecyna 539 Colobothea 539 Thyrsia 539 tribe it. Lepttjret;e 540 Leptura 540 Desmocerus 541 Vesperus 541 Rhagium 542 Rhamnusium 542 Toxotus 542 Stenoderus 542 Distenia 542 Cometes 542 Leptura proper 543 EUPODA 543 TRIBE 1. Sagrides 544 Sagra 545 Megalopus 545 Sagra proper 545 Orsodacna 545 Psammcechus 546 TRIBE II. Criocerides 546 Crioceris 546 Donacia 546 Hsemoma 547 Ptauristes 547 Crioceris proper 547 Auchenia 548 Megascelis 549 CYCLICA 549 TRIBE I. Cassidarije 550 Hispa 551 Alurnus 551 Hispa proper 551 Chalepus 552 Cassida 552 Imatidium 552 Cassida proper 552 TRIBE II. Chrtsomelik^: 553 Cryptocephalus 553 Clythra 554 Chlamys 554 Lamprosoma 555 Cryptocephalus proper 555 Choragus 555 Euryope 555 Eumolpus 556 Chrysomela 556 Colaspis 556 Podontia 556 Phyllocharis 557 Doryphora 557 Cyrtonus 557 Paropsis 557 Upamsea 557 Timarcha 558 Chrysomela proper 558 Phaedon 559 Prasocuris 559 TRIBE III. Galerucite 559 Galeruca 560 Adorium 560 Luperus 560 Galeruca proper 560 Altica 560 Octogonotes 561 XX SYSTEMATIC INDEX. (Edionychus 561 Psylliodes 561 Dibolia 562 Mtica proper 562 Longitanus 562 CLAVIPALPI 562 Erotylus 563 Erotylus proper 563 Trip lax 564 Languria 564 Phalacrus 564 Agathidium 564 Trimera. FUNGICOLJS 565 Eumorphus 565 Eumorphus propel 565 Dapsa 566 Endomychus 566 Lycoperdina 566 APHIDIPHAGI 566 Coccinella 567 Lithophilus 567 Coccinella proper 567 Clypeaster 568 PSELAPHH 568 Pselaphus 569 Chennium 569 Dionix 569 Pselaphus proper 569 Bithynus 570 Areopagus 570 Ctenistes 570 Byraxis 570 Claviger 570 Claviger proper 570 Artieerus 570 THIRD GREAT DIVISION OF THE ANIMAL KINGDOM. CRUSTACEA, ARACHNIDES, AND INSECTA: OR ARTICULATED ANIMALS WITH ARTICULATED FEET(l). These last three(2) classes of the Articulata, which were united by Linnaeus under the general name of Insecta^ are distinguished by at least six(3) articulated feet. Each articu- lation is tubular, and contains the muscles of the succeeding one, which always moves by gynglymus, that is, in but one direction. The first articulation, which attaches the foot to the body, (1) For the sake of brevity, I have designated them by the term Condylopes. This series of articulations, of which their body is composed, has been compared by some Naturalists to a skeleton, or the vertebral column. But the use of this denomination is so much the more fallacious, in as much as these articulations or pretended vertebrae are mere portions of thickened skin, and as this skin is continu- ous, simply being thinner, and almost membranous at intervals or at the joints. A general character, which serves to distinguish these animals from all other Inverte- brata, consists in their exuviability, or habit of changing their skin. The situation of the encephalon, pharynx, and eyes, as in the more elevated animals, establishes the limits of the back and abdomen, and of their respective appendages. (2) Dr Leach forms a separate class of the Myriapoda. The Arachnides Tra- cheariae, considered anatomically, might also constitute another, but they are so closely allied to the Pulmonarije in so many other particulars, that we have not thought proper to separate them- (3) Hexapoda. Those which have more than six, are termed by Savigny the Spiriopoda. I designate them more precisely by the appellation of Hyperhexa- poda, (more than six feet). Vol III. A 2 CRUSTACEA, AKACHNIDES, INSECTA. and which is composed of two pieces(l), is called the coxa, or hip ; the following one which is, usually, nearly in a hori- zontal position, the femur, or thigh; and the third, generally vertical, the tibia or leg. To these ensues a suite of small ones which touch the ground, forming the true foot, or what is denominated tiie tarsus. The hardness of the calcareous or horny(2) envelope of the greater number of these animals, is owing to that of the ex- cretion, which is interposed between the dermis and epider- mis, or what is termed in man the mucous tissue. This ex- cretion also contains the brilliant and varied colours with which they are so often decorated. They are always furnished with eyes, which are of two kinds : simple or smooth eyes(3), which resemble a very mi- nute lens, generally three in number, and arranged in a tri- angle on the summit of the head; and compound eyes, where the surface is divided into an infinitude of different lenses called facets, to each of which there is a corresponding filament of the optic nerve. These two kinds may be either united or separated, according to the genera. Whether their functions be essentially different in those cases where they are found to exist simultaneously, is a problem that remains to be solved ; but vision is effected in both of them by means differing widely from those which produce it in the eye of the Vertebrata(4). (1) In many of the Crustacea the second portion of the coxa seems to form part of the thighs. The tibia, as in the Arachnides, is divided into two joints. (2) According to M. Aug. Odierj Mem. de la Soc. d'Hist. Nat., 182u, t. I, p. 29 et seq., the substance of this envelope is of a peculiar nature, which he calls Chi- tine. He states that the phosphate of lime forms the g-reat mass of all the salts contained in the teguments of Insects, while that in the shell of the Crustacea is but trifling, though it abounds in the carbonate, which is not found in the prece- ding animals. Other observations, those of M. Straus in particular, demonstrate that the teguments here replace the skin of the Vertebrata, or that they do not form a true skeleton. Those of M. Odier also militate against all the analogies attempted upon this subject. (3) Ocelli stemmata. (4) See the Memoir of Marcel de Serres on the simple and compound eyes of Insects, Montpcllier, 1815, Svo. Also the observations of M. de Blainville on the eyes of the Crustacea, Bullet, de la Soc. Philomatique. We shall return to this subject at another period. CRUSTACEA, ARACHNIDES, 1NSECTA. 3 Other organs which for the first time are here presented to us, and which are found in two of these classes, the Crustacea and the Insecta(l), the antennae, are articulated filaments, va- rying greatly in form, and frequently according to the sex, attached to the head, appearing to be peculiarly devoted to a delicate sense of touch, and perhaps to some other kind of sen- sation of which we have no idea, but which may refer to the state of the atmosphere. These animals enjoy the sense of smell and that of hearing. Some authors place the seat of the first in the antenn3e(2), others, M. Dumeril for instance, in the orifices of the tracheae, and Marcel de Serres, &c. in the palpi ; neither of these opinions, however, are corroborated by positive and conclu- sive facts. As to the second, it is only in the Crustacea Deca- poda and some few of the Orthoptera, that we can find a visi- ble ear. The mouth of these animals presents a great analogy, which, according to Savigny(3), and at least with respect to the Hex- apoda, extends to those which can only feed by the suction of liquid aliment. Those called Tritores or Grinders {broyeurs), on account of their having jaws fitted for triturating their food, always present them in lateral pairs, placed one before the other ; the anterior pair are especially called mandibles; the pieces which (1) And even in the Arachnides, but under different forms, and with different functions. (2) As regards insects, and when they are claviform, or terminate in a club more or less developed, or furnished with numerous hairs. According to M. Robineau Desvoidy, the intermediate antennje of the Crustacea Decapoda are the olfactory organ, Bullet, des Sc. Nat.; but he adduces no one direct experiment in proof of his opinion. It would, if this were so, seem probable that in the highly carnivorous Crustacea, such as the Gecarcini and others, we should find this organ in a comparatively greater state of development, whereas the fact is directly the reverse. His ideas respecting the external composition of the Crustacea Decapoda suppose the existence of a skeleton. He should have commenced, however, by establishing the connexion of these animals with the Fishes, and not by admitting, as a positive fact, what is at least a- matter of doubt. (3) MSmoire sur Its animaux sans vertebres. The original idea was thrown out, but undeveloped, in my Hist. Gen. des Insectes. 4 CRUSTACEA, ARACHNIDES ? IXSECTA. cover them before and behind are named labia(l), and the front one, in particular, lafoum. The palpi are articulated filaments attached to the jaws or to the lower lip, and appear to be employed by the animal in recognizing its food. The form of these various organs determines the nature of the re- gimen with as much precision as the teeth of quadrupeds. The ligula, or tongue, commonly adheres to the lower lip(2). Sometimes, in the Apes and other Hymenopterous insects, it is considerably elongated, as are also the jaws, forming a sort of false proboscis (promuscis) at the base of which is the pharynx, and frequently covered by a sort of sub-labrum, styled by M. Savigny the epipharynx{3). At other times, (1) We here more particularly allude to Insects with six feet, or to the Hexa- poda. (2) Or rather labium, since the other is termed labnim. It is protected, before, by a horny production formed by a cutaneous prolongation, and articulated at the base with an inferior portion of the head called the mentum or chin. Its palpi, always two in number, are distinguished'from those of the maxillae by the epithet labial. When the latter amount to four they are designated as external and inter- nal; they are considered as a modification of the external and terminal division of the maxillae. This production, which, in his Ulonates or the Orthoptera, Fabricius termed the Galea, is still the same maxillary division, but more dilated, arched, and fitted to cover the internal division which, here, on account of its scaly consistence and of its teeth, resembles a mandible. In the last insects, and particularly in the Libellula:, the interior of the buccal cavity presents a soft or vesicular body, dis- tinct from the lip, and which, compared to the Crustacea, appears to be the true tongue labium, Fab. This part is perhaps represented by those lateral divi- sions of the ligula termed paraglossse. (See the Coleoptera Carnivora, Hydro- phili, Staphylini, the two pencil-shaped pieces that terminate the lip of the Lucani, Apiarise, &c) The above mentioned Insects, the Orthoptera and the Libellulas of Linnaeus, evidently demonstrate that this membranous and terminal portion of the inferior lip, which projects more or less between its palpi, and is particularly elon- gated in several of the Hymenoptera, is very distinct from that internal caruncle which I consider the tongue properly so called; notwithstanding this, nearly all Entomologists designate this external extremity of the lip by the name of ligula, or languette. To say, however, that the tongue properly so called, is usually so intimately connected with the lip that at the first glance they seem to be con- founded, is correct. The pharynx is situated in the middle of the anterior face of this lip a little above its root, and in the Coleoptera provided with paraglossae, at their point of union. In order to understand well the primitive composition of the under lip, it must be studied in the larvae, and chiefly in those of the Aquatic Carnivorous Coleoptera. See General Observations on Insects. (3) There is a membranous production beneath the labrum, in many Coleop- CRUSTACEA, ARACHN1DES, INSECTA. 5 in the Hemiptera and Diptera, the mandibles and maxillae are replaced by scaly pieces in the form of setre, which are re- ceived in an elongated tubular sheath, that is either cylin- drical and articulated, or formed with more or less of an elbow, and terminated by a kind of lips. In this case they constitute a true proboscis. In others that also live by suction, the Le- pidoptera, the maxillae alone are greatly elongated and united, producing a tubular setiform body, resembling a long, slen- der, and spiral tongue (or the spiritrompe, Lat); the re- maining parts of the mouth are considerably reduced. Some- times again, as in many of the Crustacea, the anterior feet approach the maxillce, assume their form, and exercise part of their functions the latter are then said to be multiplied. It may even happen that the true maxillcE become so much re- duced, that the maxillary feet supply their place in toto. Whatever be the modifications of these parts, however, they can always be recognized and referred to a general type(l). tera, which appears to me to be analogous to the epipharynx. The labrum is to it, what the mentum is to the labium. (1) It is only by a comparative and gradual study of the mouth of the Crus- tacea, that Ave can acquire correct and exact ideas respecting the various trans- formations of these parts, and the means of establishing - , if not a certain, at least a probable general concordance between these various organs in the three classes. The mandibles, maxillx, and the labium, are in fact, a sort of feet' appro- priated to the masticatory or buccal functions, but susceptible of being so modified as to become organs of locomotion. This principle even extends to the anten- nae, or at least to the two intermediate ones of the Crustacea. By adopting it, we* are enabled to reduce the composition of these organs to one general type, and we shall hereafter see that, in this respect, neither the Arachnides nor Myriapoda present any anomaly. CLASS I. CRUSTACEA. The Crustacea are articulated animals, with articulated feet, respiring by means of branchiae, protected in some by the bor- ders of a shell., and external in others, but which are not in- closed in special cavities of the body, and which receive air from openings in the surface of the skin. Their circulation is double, and analogous to that of the Mollusca. The blood is transmitted from the heart, which is placed on the back, to the different parts of the body, whence it is sent to the bran- chiae, and thence back again to the heart(l). These branchiae, sometimes situated at the base of the feet, or even on them, and at others on the inferior appendages of the abdomen, either form pyramids composed of laminae in piles, or bristled with setos or tufted filaments of simple ones, and even appear in some cases to consist wholly of hairs. Some of the Zootomists, Baron Cuvier in particular, had already made known to us the nervous system of various Crus- tacea of different orders. The same subject has lately been thoroughly examined by Messrs Victor Audouin and Milne Edwards in their third Memoir on the Anatomy and Physio- logy of these animals Ann. des Sc. Nat. XIV, 77, and all that is now wanting to complete their researches, is the pub- lication of those made by M. Straus on the Branchiopoda and the Limuli in particular, which they have not noticed. (1) See the order Decapoda. CRUSTACEA. 7 "The nervous system of the Crustacea submitted to our observation, say they, presents itself in two very different as- pects, which constitute the two extremes of the modifications visible in that class. Sometimes, as in the Talitrus, this ap- paratus is constituted by numerous similar nervous inflations, arranged in pairs, and united by cords of communication in such a way as to form two ganglionic chains, separated from each other and extending throughout the length of the animal. At others, on the contrary, it is solely composed of two gan- glions or knotty enlargements, dissimilar in form, volume, and arrangement, but always simple and azygous, and situated, one in the head and the other in the thorax. Such is the case in the Maia. u These two modes of organization, at the first glance, cer- tainly seem essentially different, and if the study of the ner- vous system of the Crustacea were limited to these two ani- mals, it would be extremely difficult to recognize the analogy between the central nervous mass in the thorax of the Maia, and the two ganglionic chains which occupy the same region of the body in the Talitrus. But if we remember the various facts detailed in this memoir, we necessarily arrive at this re- markable result." They were led to it by the exact and careful study of the nervous system of various intermediate Crustacea, forming so many links of the series, such as the Cymothooe(l), the Phyllo- som8e(2), Astacus(3), Paloemon and Palinurus. They have also supported their positions by the observations of Cuvier and those of M. Treviranus. The consequence deduced by them is, that notwithstanding this difference, the nervous system of the Crustacea is formed of the same elements, which, insulated in some and uniformly distributed throughout the length of the body, present in others, various degrees of centralization, at first from without inwardly, and then in a longitudinal di- (1) Isopoda. (2) Stomapoda. (3) For this subgenus and the two following subgenera see the Decapoda Macroura. 8 CRUSTACEA. rection ; and that finally, this approximation in all directions is carried to its extreme point, when it is reduced to a single nucleus in the thorax as in Cancer properly so called, or the Brachyura. Of all the Decapoda Macroura examined by Messrs Audouin and Edwards, the Palinurus was found to have the venous system most centralized ; and in fact, that animal in our system is but little removed from the Brachyura. But this should not be the case with Palsemon and the Asta- cini, for according to them the former approximates more closely in this respect to Palinurus than the latter, while in our arrangement the second precede the first, a disposition which appears to us to be founded on several very natural characters. The Crustacea are apterous or deprived of wings, furnished with compound eyes, though rarely with simple ones, and usually with four antennse. They have mostly the Psecilo- poda excepted three pairs of jaws, the two superior ones, designated by the name of mandibles, included ; as many foot- jaws^), the last four of which, however, in a great many in- stances, become true feet ; and ten feet properly so called, all terminated by a single small nail. When the last two pairs of foot-jaws exercise the same functions, the number of feet is in- creased to fourteen. The mouth, as in insects, presents a labrum and a ligula, but no lower lip properly so called, or comparable to that of the latter ; the third pair of foot-jaws, or the first, closes the mouth externally, and replaces that part. The sexual organs, at least those of the males, are always double, and situated on the breast or at the inferior origin of that posterior and abdominal portion of the body commonly (1) Auxiliary jaws, as they are termed by M. Savigny, at least when speaking' of the Crustacea Decapoda. As the two superior ones, in the Amphipoda and Isopoda, form a sort of lip, he there calls them the auxiliary lip. He distinguishes the jaws in Phalangium, a genus of Arachnides, as principal jaws,- those which are attached to the palpi false palpi, according to him; and as supernumerary jaws, those which are attached to the first four feet. Those parts of the same animals which have been considered as mandibles, are his mandibules succtdanes. He ad- mits of two auxiliary lips in the Scolopendne. CRUSTACEA. 9 called the tail, and never posteriorly. Their envelope is usually solid, and more or less calcareous. They change their skin several times, and generally preserve their primitive form and natural activity. They are mostly carnivorous and aquatic, and live several years. They do not attain their adult state until after casting their skin a certain number of times. With the exception of a few in which these changes somewhat in- fluence their primitive form and modify or augment their locomotive organs, they are at birth, size apart, such as they are always to remain. Division of the Crustacea into Orders. The situation and form of the branchiae, the mode in which the head is articulated with the trunk(l), the mobility or fix- edness of the eyes(2), the organs of manducation, and the tegu- ments, constitute the basis of our divisions, and give rise to the following orders(3). We divide this class into two sections, the Malacostraca, and the Entomostraca(4). The first are usually furnished with very solid teguments, of a calcareous nature, and with ten or fourteen feet(5), gene- rally unguiculated. The mouth, situated in the ordinary (1) "With respect to this term, and that of thorax, which are frequently em- ployed in an arbitrary manner, see our general observations on the class of Insects. (2) These organs are either pediculated and movable, or sessile and fixed. It is from this character that Lamarck has divided the Crustacea into two great sec- tions, the Pediocles and the Sessiliocles; for which denominations, but restricting its application to the Malacostraca, Doctor Leach has substituted those of Podop- tlialma and Edriopthalma. Gronovius was the hrst who had recourse to this dis- tinction. (3) Although we possess but few observations on the nervous system of the Crustacea, all those which have been made support the truth of our divisions. (4) They might be still further divided into the Dentata and the Edentata, ac- cording to the presence or absence of the mandibles. Jurine, Jun., has already proposed these divisions in his excellent Me moire sur l'Argule foliace. (5) The four anterior, when there are fourteen, are formed by the last four pos- terior foot-jaws. In the Decapoda, the six foot-jaws belong to the mouth, and per- form the office of maxillx. Vol. III. B 10 CRUSTACEA. place, is composed of a labrum, tongue, two mandibles (fre- quently furnished with palpi), and two pairs of maxillae co- vered by the foot-jaws. In a great number each eye is placed on an articulated and movable pedicle, and the branchiae are concealed under the lateral margins of the upper or lower shell ; in the others they are usually placed under the post- abdomen. This section consists of five orders : the Decapoda, Stomapoda, L^emodipoda, Amphipoda, and the Isopoda. The four first embrace the genus Cancer of Linnaeus, and the last his Oniscus. The second, the Entomostraca, or " Insects with shells" of Muller, is formed of the genus Monoculus, Lin. Here the teguments are horny and very thin, while a shell, resem- bling a buckler, composed of from one to two pieces, covers or incloses the body of the greater number. The eyes are almost always sessile, and frequently there is but one. The feet, the number of which varies, are mostly fitted for nata- tion, and without a terminal nail. Some of them, having an anterior mouth composed of a labrum, two mandibles rarely furnished with palpi, a tongue, and one, or at most two pairs of jaws, of which the external ones are naked or are not co- vered by the foot-jaws, approximate to the preceding Crusta- cea. In the other Entomostraca, which seem to approach the Arachnides in several particulars, the organs of manducation are sometimes simply formed by the coxae of the feet, pro- jecting and arranged like lobes bristling with small spines round a large central pharynx. At others they either com- pose a little siphon or beak, used for suction, as in several Arachnides and Insects, or they are wholly (or nearly so) in- visible externally, either because the siphon is internal, or be- cause the suction is produced in the manner of a cup. The Entomostraca are thus dentated or edentated. The first will form our order of the Branchiopoda(I), and the (1) In my work entitled Families Nat. du Regne Animal, the Entomostraca are divided into four orders: the Lophykopoda, Phyllopoha, Xiphosuka, and the Si- PHOSOSTOMA. CRUSTACEA. 11 second that of the P;ECILopoda, which in the first edition of this work were a mere section of the preceding order. The singular fossils called Trilobites, of which M. Brong- niart has given an excellent Monograph, being considered by him, as well as by many other naturalists, as Crustacea al- lied to the Entomostraca, we will briefly speak of them after we have done with the latter. 12 CRUSTACEA. FIRST GENERAL DIVISION. MALACOSTRACA. The Malacostraca naturally divide themselves into those whose eyes are placed on a movahle pedicle, and those in which they are sessile and fixed. a. Eyes placed on a movable and articulated pedicle. Eyes(l) placed on a movable pedicle composed of two arti- culations, and received into fossilise, distinguish the Decapoda and Stomapoda from all the others. Anatomically considered, they appear to be still further removed from them, Lecons d'Anat. Compar., Cuv.; Ann. des Sc. Nat., t. XI, inasmuch as they are the only ones that present sinuses in which the venous blood is collected previous to its transmission to the branchice on its return to the heart. The Decapoda and Stomapoda resemble each other in se- veral characters common to both. A large plate called a shell covers a greater or less extent of the anterior portion of their body. They all have four antennse(2), the middle ones of (1) Behind the cornea, according- to Blainville, is a choroides perforated with numerous holes; then a true crystalline, resting- on a nervous ganglion, and divided into a multitude of little fasciculi. (2) We must distinguish the peduncle stipes, and the stem caulis, funiculus. The peduncle is thicker, cylindrical, and composed of three joints, a number which seems peculiar to these organs in their imperfect or rudimentary state. The stem is setaceous, and divided into a variable number of very small joints. That of the external antennre is simple, but that of the interior ones consists of at least two filaments, and in several of the Decapoda Macroura, of three. Passing' gradually from these latter to the Brachyura, the antennae become shortened, so that, in several of the Quadrilatera, the lateral ones, at least, are very small. In this case the two terminal divisions of the intermediate ones form a sort of bifurcated forceps, or unequal and articulated fingers. M.VLACOSTRACA. 13 which are terminated by two or three filaments; two mandi- bles, each of which, at its base, bears a palpus that is divided into three joints and usually laid on it; a bilobate tongue; two pairs of jaws ; six foot-jaws, the four posterior of which, in some, are transformed into claws ; and ten feet, or fourteen, in those where the four foot-jaws have that form. In the greater number the branchiae, of which there are seven pairs, are concealed under the lateral margin of the shell: the two anterior pairs are situated at the origin of the four last foot-jaws, and the others at that of the feet properly so called. In the other Crustacea they are annexed, in the shape of tufts, to five pairs of paddles (feet) placed under the post-abdomen. The under part of this posterior portion of the body is similarly furnished, in the others, with four or five pairs of bifid appendages. ORDER I. DECAPODA. The head, in the Decapoda, is closely joined to the thorax, and covered with it by a shell, entirely continuous, but that most frequently exhibits deep lines dividing it into various regions which indicate the places occupied by the principal internal organs(l). The mode of their circulation presents characters which distinguish them from the other Crustacea. (1) M. Desmarest, in his Histoire Naturelk des Crustace's Fossiles, and in his Considerations Generates sur la Classe des Crustacea, lias presented us, in relation to this point, with an ingenious nomenclature, based on the concordance of the portions of the external surface of the shell with the organs they cover. But, in addition to the fact that the shell of several Decapoda presents no impressions, or has them nearly obliterated, these denominations may be replaced by others more simple, more familiar, and relating 1 to these same organs; as the middle or centre, the anterior and posterior extremities, the sides, &c: it appears useless to increase our nomenclature in this case. 14 CRUSTACEA. The circumscribed heart(l),of an oval form and with muscu- lar parietes, gives origin to six trunks of vessels, three of which are anterior, two inferior, and the sixth posterior. Of the three anterior arteries, the median the ophthalmic is distributed almost exclusively to the eyes ; the two others the antennarics spread over the shell, the muscles of the sto- mach, a portion of the viscera and the antennae ; the two in- ferior ones the hepatics transmit blood to the liver; the last the sternal is the most voluminous of the three, and arises from the posterior part of the body, sometimes on the right side and at others on the left; its chief course is to the abdomen, and to the organs of locomotion. It gives origin to a great number of large vessels, among which we should par- ticularly observe the one called by M. Audouin and Edwards the superior abdominal, because it arises from the posterior part of that artery, at a short distance before the articulation of the thorax with the abdomen, vulgarly termed the tail, and because it soon dips into the abdomen tail, where it divides into tw T o large branches, running backwards, becoming gra- dually smaller and terminating at the anus. The blood which has nourished these various organs, and thus become venous, collects from all quarters in two large sinuses(2), one on each (1) These observations are extracted from the excellent Memoir of Messrs Audouin and Edwards, published in the Jinn. d'Hist. Nat., t- XI, 283 314, and 352 393. See also the Mem. duMus. d'Hist. Nat., where M. Geoffroi Saint-Kil- aire has inserted the results of his curious researches on the solids, and on the cir- culation of the Lobster. (2) These learned naturalists compare them to the two lateral hearts of the Ce- phalopoda, and the analogy has been admitted by Baron Cuvier in his general Re- port on the transactions of the Acad. Roy. des Sc, for 182"; but the idea had been communicated by me to M. Audouin, and was a necessary consequence of my theory of the circulation of the blood in the Crustacea, published in a note of my Esquisse d'une Distribution Generate du Begne Animal, p. 5. As the writers alluded to have taken no notice of what I have stated in this particular, both in the pam- phlet quoted, and in my work on the " Families of the Animal Kingdom," I beg leave to produce that note. " I submit the following opinion to the judgment of Zootomists, and of M. Cuvier in particular, viz. that in those of the Vertebrata possessed of a circulation, the organ called heart represents, in its functions, a left ventricle, the arterial and dorsal trunk of Fishes and of the larvae of the Ba- trachians; that one or two arteries, which in the Cephalopoda have the form of DECAPODA. 15 side and above the feet, and formed of venous sacs united in a longitudinal series, or like a chain. It is thrown into an external vessel efferent of the branchiae, where it is re- newed and becomes arterial ; thence proceeds into an internal vessel afferent; and finally seeks the heart through canals branchio- cardiac laid beneath the arch of the flanks. All the canals of a side unite in one large trunk, and open into the lateral and corresponding part of the heart by a single orifice, the folds of which form a double valve that opens to allow the transit of the blood from the branchiae to this viscus, but pre- vents a retrograde motion by closing. Examined internally, the heart exhibits numerous fasciculi and muscular fibres, va- riously intercrossed and forming several small chambers before the orifices of the arteries. These chambers are so many small auricles, which communicate freely with each other when it dilates, but appear to form a similar number of little cells for each vessel when it contracts, their capacity being proportioned to the quantity of blood in their peculiar vessels. These vessels debouche in the interior of the heart by eight openings, the two lateral valvular ones above mentioned in- cluded. Such, with the exception of some modifications^ ), is the general system of the circulation in the Decapoda. The superior face of the brain(2) is divided into four lobes, each of the two middle ones furnishing from its anterior mar- gin an optic nerve that plunges directly into the pedicle of the eye and there divides into numerous filaments, each of which is destined to a facet in the cornea of that organ. hearts, replace the right ventricle. The focus of the circulation, highly concen- trated in the first of the Vertebrata, thus becomes gradually weaker, so that finally there is no circulation whatever. The dorsal vessel of Insects would then be the mere rudiment of the heart of the Mollusca and Crustacea." I will add, that twenty-five years ago, in my Hist. Nat. des Crust, et des Insectes, I rectified the error of Hcesel respecting the nervous cord of the spinal marrow, which had been taken for a vessel. (1) See general observations on the family of the Macroura. (2) These observations are extracted from the Legons d'Anatomie Compare of Baron Cuvier. For other details and particular facts see the Memoir of Messrs Audouin and M. Edwards, loc. cit. 16 CRUSTACEA. The inferior face of the brain produces four nerves, which belong to the antennae, and that also give off some twigs to the neighbouring parts. Two nervous and very long cords, em- bracing the esophagus laterally and uniting beneath it, arise from its posterior margin. There, as in the Brachyura, this union only takes place in the middle of the thorax, the me- dulla then assuming the form of a ring whose proportions are eight times larger than those of the brain : six nerves on each side arise from this ring ; the anterior ones belong to the parts of the mouth, and the five others to the five feet of the same side. From the posterior margin arises another nerve which runs to the tail, without producing any sensible ganglion, and that apparently represents the ordinary nervous cord. Here, as in the Macroura, each of the two nervous cords, previous to uniting beneath the esophagus, and at about the middle of its length, gives off a thick nerve for the use of the mandibles and their muscles. United, they form a first sub-cervical ganglion that distributes nerves to the maxillae and the foot- jaws(l); they afterwards continue approximated throughout their length, presenting eleven successive ganglions, each of the five first furnishing nerves to as many pairs of feet, and the remaining six those of the tail; that of the Pagurus has some ganglions less, thus appearing to form the passage from the Brachyura to the Macroura. M. Serres thinks that he has recognized in these Decapoda, vestiges of the great sym- pathetic (2). The lateral margin of the shell is bent under, to cover and protect the branchiae, leaving an opening anteriorly for the (1) According to M. Straus, the anterior division of the body of the Liinuli, that which is covered by a semi-lunar buckler, presents, besides the brain, no other ganglion but this, whence we may infer that the inferior organs of locomo- tion correspond to the parts of the mouth in the Decapoda, Stomapoda, and even in the Arachnides, and that those of the other division of the body, or of the second buckler, are analogous to the feet of the same Decapoda. (2) Messrs Audouin and Edwards have observed in the Maia and in the Palinu- rus a nerve analogous to the one called by Lyonet, in his Jnatomie de la Chenille du Saule, "recurrent." The discovery of the other gastric nerves is also due to them. DEC APOD A. 17 passage of water. Sometimes, see Dorippe the posterior and inferior extremity of the thorax has two peculiar aper- tures for that purpose. The branchiae are situated at the origin of the last four foot-jaws and feet; the four anterior ones have less extent. The six foot-jaws are all of a different form, are applied to the mouth, and divided into two branches, the exterior of which resembles a small antenna, formed of a pe- dicle, and a setaceous and pluri-articulate stem it has been compared to a whip, palpus flagellifor?nis(l). The two an- terior feet, and sometimes the two or four following ones, are in the form of claws. The penultimate joint is dilated, com- pressed, and in the form of a hand ; its inferior extremity is lengthened into a conical point, representing a sort of finger, opposed to another formed by the last joint, or the tarsus proper. This one(2) is movable, and has received the name of thumb pollex ; the other is fixed, and considered as the index index. These two fingers are also called mordaces. The last is sometimes very short, and has the form of a sim- ple tooth ; in this case the other is bent underneath. The hand with the fingers constitutes our forceps properly so called. The preceding, or antepenultimate joint is termed carpus. The respective proportions and the direction of the organs of locomotion are such, that these animals can walk sideways or backwards. With the exception of the rectum, which opens at the end of the tail(3), all the viscera are contained in the thorax, so that this portion of the body represents the thorax and the greater part of the abdomen of insects. The stomach, sup- (1) There is a long, tendinous and hairy lamina at its base. (2) The hand being 1 placed on its edge, the finger is uppermost. (3) This suite of segments which, in the Crustacea of the first orders, imme- diately succeed those to which the five last pairs of feet are attached, compose what I have termed the post-abdomen. The appellation of tail usually affixed to it, and which, in order to accommodate ourselves to common parlance, we have retained, is very improper; it can only apply to the posterior terminal appendages of the body which extend considerably beyond it. See my Fam. Nat. du Regne Anim., p. 255, et seq. Vol. III. C 18 CRUSTACEA. ported by a cartilaginous skeleton, is armed internally with five bony and notched appendages, which completes the tri- turation of the aliment. In it, in the moulting season, which arrives near the end of spring, we observe two calcareous bo- dies, round on one side and flat on the other, commonly called crabs' eyes, that disappear after the change is completed, thereby inducing us to believe that they furnish the material for the renewal of the shell. The liver consists of two large clusters of blind vessels, filled with a bilious humour, which they pour into the intestine, near the pylorus. The alimen- tary canal is short and straight. The flanks present a range of holes situated immediately at the insertion of the branchiae, but which can only be seen by removing those organs. The under shell, viewed internally, at least in several large spe- cies, exhibits transverse cells formed by crustaceous laminae, and separated in their middle by a longitudinal range of the same nature. The sexual organs of the male are situated near the origin of the two posterior feet. Two articulated pieces, of a solid consistence, and resembling horns, stylets, or setaceous an- tennae, placed at the junction of the tail with the thorax and replacing the first pair of subcaudal appendages, are regarded as the male organs of copulation, or at least as their sheaths. But, according to our observations on various Decapoda, each of them consists of a little membranous body, sometimes seta- ceous, and at others filiform or cylindrical, that projects from a hole situated at the articulation of the hip of the two poste- rior feet, with the lower shell. The two vulvae are placed on this piece, between those of the third pair, or on their first joint, a disposition depending on the widening and narrowing of the lower shell. Copulation takes place, ventre a ventre, These animals grow but slowly, and live a long time. It is among them that we find the largest and most useful species, but their flesh is not easily digested. The body of some Pali- nuri attains the length of a metre. Their claws are efficacious weapons, and have such power in large individuals, that they have been seen to seize a Goat, and drag it from the shore. DECAPODA. 19 They usually inhabit water, but do not instantly perish when deprived of it; some species even pass a part of their lives on land, only visiting the water in the nuptial season, and for the purpose of depositing their spawn. Even they are compelled to fix their domicil either in burrows, or in cool, damp places. The Decapoda are voracious and carnivorous. Certain spe- cies even penetrate into cemeteries, and devour the dead. Their limbs are regenerated with surprising promptitude, but it is requisite that the fracture be at the junction of the arti^ dilations, and when accident determines it otherwise, they know how to apply a remedy. When they wish to change their skin, they seek a retired and solitary spot, in order to be sheltered from their enemies, and to remain at rest. When the change is effected, their body is soft, and has a more ex- quisite flavour. A chemical analysis of the old shell proves it to be formed of the carbonate and phosphate of lime, united in different proportions with gelatine. On these proportions depends the solidity of the shell : it is much less thick and flexi- ble in the latter genera of this order, and further on, it becomes almost membranous. M. de Blainville has observed that the shell of the Palinurus is composed of four superincumbent lay- ers, the superior and two inferior of which are membranous ; the calcareous matter is interposed between them, forming the fourth. Exposed to heat, the epidermis becomes of a more or less vivid red, the colouring principle being decomposed by boiling water; other combinations of this principle produce, in some species, a very agreeable mixture of colours, that fre- quently border on blue or green. The greater number of fossil Crustacea hitherto discovered belongs to the order of the Decapoda. Among those of Eu- rope, the oldest approach to species now living in the vicinity of the tropics; the others, or more modern ones, are closely allied with the living species of Europe. The fossil Crustacea of the tropical regions, however, appear to me to bear the closest similitude to several of those now found there in a liv- ing state, a fact of much interest to the geologist, should the study of the fossil shells of those countries, collected from the deepest strata, furnish a similar result. 20 CRUSTACEA. FAMILY 1(1). BRACHYURA. Kleistagnatha, Fab. Tail shorter than the trunk, without appendages or fins at the extremity, and doubled under, in a state of rest, when it is received in a fossula on the chest. Triangular in the males, and only furnished at base with four or two appendages, in the form of horns, the superior of which are the largest, it becomes widened? and convex in the females(2), presenting beneath four pairs of double hairy filaments(3), destined to support the ova, and analogous to the sub-caudal natatory feet of the Macro ura, and others. The vulvae are two holes situated under the pectus, between the third pair of feet. The antennae are small : each of the intermediate ones, usually lodged in a fossula under the ante- rior edge of the shell, terminates in two very short filaments. The ocular pedicles are generally longer than those of the Decapoda Macroura. The auricular tube is almost always stony. The first pair of feet terminate in a forceps or claw. The branchiae are disposed on a single range, in the form of pyrami- dal ligulas, composed of a multitude of leaflets piled one on another, in a direction parallel to their axis. The foot-jaws are generally shorter and broader than in the other Decapoda, the (1) The sections thus named are based on an ensemble of important anatomical characters, and generally correspond to the Linnsean genera, and sometimes also to those established by Fabricius in his earlier works. These families are more extensive than the sections thus named in my other writings: but if they be con- sidered as first divisions of orders, and if what I have termed tribes be considered as families, it will be seen that the method is essentially the same. There is, then, the opinions of others to the contrary notwithstanding, no real discrepance in this respect. On the same principle, the subgenera, with the exception of some whose characters are too minute or too slightly marked, will become genera in a more detailed and special system. (2) The apparent number of segments, which is usually seven, sometimes also varies according to the sex; it is less in the females. Dr Leach has made great use of this consideration, which appears to us of but little importance, and opposed to the natural order. (3) Several of these filaments exist in the males, but in a rudimental state. DECAPODA. 21 two external ones forming a sort of lip(l ). Their nervous system also differs from that of the Macroura(2). This family, as in several of the systems anterior to the distribution of these animals by Daldorf, might constitute but one genus, that of Cancer, Lin. In the greater number, all the feet are attached to the sides of the pectus, and are always exposed; this is the case in the first five sec- tions. The first, or that of the Pinnipedes(3), to this character, adds that of having the last feet, at least, terminated by a very flat or fin- like joint that is oval or orbicular and broader than the same joint of the preceding feet, even when they also are shaped like a fin. They seldom frequent the coast, and are generally found in the high (1) Those of the Macroura are longer and narrower. It is on this difference that Fabricius established his order of the Exochnata. (2) See general observations on the Decapoda. (3) This systematic arrangement of the Brachyura is artificial, or but little natural in some respects; in consequence of which, we have somewhat altered it in our Families Naturelles du Regne Animal. The Quadrilatera compose our first tribe, at the head of which are the Ocypodamd other Land-Crabs, ending with the River-Crabs, or the Telphusx. The Arcuata form the second. That of the Cryptopoda appearing to us more closely allied to the preceding one than the Triangularia, will immediately follow, and be the third, and not the fourth, as in this method. Immediately after the Arcuata we will place those genera whose claws are in the form of a crest, whose lateral antennae are always very short, and the third articulation of whose foot-jaws is triangular, and frequently entire, or without any emargination; such are the Hepati, Matutse, Ovithyise, and Mursix. Brachyura approaching the latter in the form of the same articulation, but whose claws differ, and where the lateral antenr.se are salient, advanced, and fre- quently hairy, such as the Tkisc, Pirimelse, and Atelecycli, will immediately pre- cede these latter subgenera. As the Telphusae seem to be connected with the Eriphiae and the Filumni, and as from these we naturally pass to Cancer properly so called, or the Cancer, Fab., it follows that the Portuni and other natatory Ar- cuata should be at the head of this tribe. Then follow the Orbicularia, the Triaxgularia, and the Notofoda. But of these the Dromiac and the Dorippes should be placed higher in the scale. The Ilomoke, Lithodes, and Raninse, appear tome to be of all the Brachyura, those which are most closely allied to the Mac- roura. The external foot-jaws of the Homolae and of the Lithodes greatly resem- ble those of the Macroura by their length and projection. Although we have divided the Decapoda into two genera only, in order to con- form to modern systems, and to diminish the number of subgenera, our sections may be converted into tribes, corresponding to as many subgenera, to be after- wards divided into various subgeneric sections. 22 CRUSTACEA. seas. With the exception of the Orithyiae, we observe but five dis- tinctly marked segments in the tail of the males, while that of the females presents seven. We will begin with those in which all the feet, except the claws, are natatory. Matuta, Fabr. The Matutae have an almost orbicular shell armed on each side with a very stout tooth in the form of a spine; the superior edge of the hands dentated like a crest, and their external face studded with pointed tubercles; the third joint of the external foot-jaws, without any apparent emargination, terminates in a point, so that it forms, with the preceding joint, an elongated and almost right- angled triangle. The external antennae are very small, and the ocular pedicles slightly arcuated. De Geer mentions a species Cancer latipes, which he says is from the American seas, and has its front terminated by a straight and entire margin. All those we have seen, how- ever^), were brought from the East, and the middle of that margin always presents a bidentated or emarginated projection. The Polybius, Leach, Is allied to the Portuni, but the shell is proportionably narrower and more rounded; the sides are merely furnished with ordinary teeth. The third joint of the external foot-jaws is obtuse and emar- ginated. The eyes are much thicker than their pedicles, and glo- bular. But a single species is as yet known(2); it was found on the coast of Devonshire, and has also been observed by M. D'Or- bigny on the sea-coast of the western departments of France(3). In all the following swimmers, the two posterior feet only are formed like fins(4). We may first separate those whose shell is almost ovoid and trans- (1) M. victor, Fab.;Herbst., VI, 44r.M.planipes, Fab.; Hcrbst., xlviii, 6; M. lunaris, Leach, Zool. Miscell., cxxvii, 35, var.; M. Pcrom'i, lb., tab., ead., ]_2. Perhaps we should refer the fossil species called by M. Desmarest, Portune d'Hericart, Hist. Nat. des Crust., Fobs. V, 5, to this genus, or the Mursia, Leach. (2) Polybius Hensloicii, Leach, Malac. Brit.j IX, B. (3) The tarsi of the intermediate feet of the Portumni, Leach, are almost com- pressed into a fin; they might be placed after the Polybii. (4) Always wider and more oval than the preceding tarsi. DECAPODA. 23 versely truncated before, and where the tail of the males (the only- sex known) consists of seven distinct segments. Such'is the Orythyia, Fabr. The only species known, Orith. mamillaris, Fabr., Cancer bimaculatus, Hcrbst., XVIII, 101, is found in the sea of China, or at least forms a part of the collections of Insects sold by its inhabitants to foreigners. The ocular pedicles are longer in proportion than those of the Portuni. The shell of the last swimmers is much wider before than behind, forming either the segment of a circle narrowed towards the tail and truncated, or a trapezium, or is almost in the shape of a heart. Its greatest transverse diameter generally surpasses the opposite one. There are but five segments in the tail of the males, instead of the seven found in that of the females, the number usually pecu- liar to the tail of the Decapoda; the third and the two following ones are confounded or form but one; frequently, however, traces of them are discovered, at least on the sides. We will first separate those whose eyes are supported by very long and slender pedicles, arising from the middle of the anterior margin of the shell, extending to its lateral angles, and received into a groove run under the edge. Such is the Podophthalmus, Lam., Where the shell forms a transverse trapezium, wider and straight before with a long spiniform tooth behind the ocular cavities. The claws are elongated, spiny, and similar to those of most of the spe- cies of the genus Lupa, Leach. The only living species known(l) inhabits the coasts of the Isle of France and those of the neighbouring seas. The valuable cabinet of one of the most learned fossil con- chylidogists of Europe, contains an internal cast of a fossil Po- dophthalmus, to which M. Desmarest has affixed the name of its possessor, M. de France(2). The ocular pedicles of the other Crustacea, belonging to this sec- tion, are short, occupy but a very small portion of the transverse diameter of the shell, are placed in oval cavities, and resemble, generally, those of the ordinary Crabs with which these swimmers (1) Podophthalmus spinosus, Latr., Gener. Crust, et Insect., I, 1, and II, 1; Leach, Zool., Miscell. cxlviii; Portunus vigil, Fab. (2) Hist. Nat. des Crust. Foss., V, 6, 7, 8. 24 CRUSTACEA. are almost insensibly connected. They may all be united in one single subgenus, that of Portunus, Fab. Certain species(l) peculiar to the Indian Ocean, such as the Ad- mete, Herbst., LVII, 1, are distinguished from all the following ones by their shell, which is of a transversely quadrilateral form, narrowed posteriorly, and whose ocular cavities occupy its anterior lateral angles; the eyes are thus separated by an interval almost equal to the greatest width of the shell. The insertion of the lateral antennas is at a considerable distance from these cavities. Other species, whose shell forms the segment of a circle, poste- riorly truncated and widest in the middle, are remarkable for the length of their claws, which is at least double that of the shell, Each side presents nine teeth, the posterior largest and spiniform. The tail of the males is frequently very different from that of the females. These Portuni constitute the genus Lupa, Leach, and are mostly of a large size and foreign to Europe. One species, however, is found in the Mediterranean^). A third division will consist of species analogous to the last in the form of their shell, but whose lateral teeth, usually five in num- ber, are nearly equal, or where, at least, the posterior tooth differs but slightly from the preceding ones; the length of the claws does not much exceed that of the shell. Those which have from six to nine teeth on each side are exotic. The Portunus tranquebaricus, Fabr., Herbst, Cane, XXXVIII, 3, is the only one known that has nine equal teeth on each lateral edge; it is large, and is much esteemed as food. We suspect the P. leucodonte, Desmar., Hist. Nat. des Crust. Foss., VI, 1 3, is the same species in a fossil state; it is also from India. The following species, all from European seas(3), have five teeth on each lateral edge of the shell. (1) Genus Thalamita, Lat. (2) Portunus Dufourii, Latr., Nouv. Diet. d'Hist. Nat., Ed. II. This species, figured in the Diet. Class. d'Hist. Nat., closely approaches the Cancer hastatus, Lin., which he says is found in the Adriatic. The following are to be referred to the same division: Cancer pelagicus, Herbst., lviii, 55, C. forceps, Id., Iv, 4; Leach, Zool. Miscell., liv; C. sanguinolentus, Herbst., VIII, 56, 57; C. cedonulli, Id., xxxix; C. reticulatus, lb., 1; C hastatus, lb., Iv, 1; C. menestho, lb., 3; C. ponticus, lb. 5. (3) For the Mediterranean species see Petagna, Rissoand Olivi; for those on the western coast of France and the British seas, the Catalogue Mtfhodiquc des Cms- DECAPODA. 25 P. puber, Fab.,: Cancer puber, L.; Ptnn. Brit. Zool.,IV,iv, 8; Herbst., VII, 59; Leach, Malac. Brit., VI. Covered with a yellowish down; eight small teeth between the eyes, the two middle ones longest, obtuse and divergent; claws sulcated, armed with a stout dentated tooth on the inner side of the carpus, and from one joint to the following one or the hand; fingers blackish. This species is usually called in France, where its flesh is considered a delicacy, VEtr'dle. P. corrugatus; Cancer corrugatus, Penn. Brit. Zool., IV, pi. v, 9; Leach, Malac. Brit., VII, 1, 2. The shell rugose, covered with a yellowish down, and furnished with three equal, and almost lobuliform teeth in front; the three posterior teeth of the lateral margins very sharp and spiniform. P. mamas; Cancer mccnas, L., and Fab. This common spe- cies of the French coast, called Crabe enrage, appears to me to belong to the Portuni, rather than to the Crabs properly so called; its posterior fins are only somewhat narrower. Such was the first opinion of Dr Leach, who subsequently made a peculiar genus for it called Carcinus, (Malac. Brit., XII, tab. v). It also has five teeth on each side, and a similar number in front, the internal oculars included. The top of the shell is glabrous, finely shagreened, with deeply impressed lines. The tarsi are striate; the upper edge of the hand is so compressed as to form a rounded ridge, terminated by a small tooth; a second but stronger one is observed on the inner side of the preceding joint; fingers striate, and almost equally dentated, with a black- ish tip. A fossil species is found in the marly limestone of Monte- Bolca, which, according to Desmarest, Hist. Nat. des Crust. Foss., p. 125, is closely related to the mosnas. In the Portunus Rondelelii, Risso, there are no teeth in front. The one he calls longipes, presents the same character, but its feet are longer in proportion than those of other analogous spe- cies. We will form a fourth division with the subgenus. Platyonichus, Lat. Which name has replaced that of Portumnus, Leach, on account tacts du departement du Calvados," by ]?rebisson,'and especially the excellent work of Dr Leach, Malacostraca Podophthalmia Britanniw. M. Desmarest has well de- veloped the system of this author in his Considerations Generates sur les Crustacfs, an extremely useful book to those who make this branch of Zoology their study. See also our article Portune, Encyc. Methodique. Vol. Ill D 26 CRUSTACEA. of the too great similarity between the latter and the word Portunus already adopted. Here the shell is at least as long as it is broad and almost cordate. All the tarsi of the feet, the claws excepted, terminate in a small, semi-elliptical, elongated and pointed lamina ; the index is strongly compressed. This division also comprises but a single species, the Cancer latipes, Plancus, De Conchis minus notis III, 7, B, C, and which has also been figured by Leach Malac. Brit., IV. There are three teeth front, and on each lateral edge five(l). From the swimmers we pass to those whose feet all terminate in a point, or conical and sometimes compressed tarsus, but never form- ing a fin properly so called. Those of them whose shell is tapering, forming the arc of a circle before, and narrowed and truncated be- hind, in which the claws of both sexes are alike, where the number of the caudal segments is the same as in the Portuni, and which, with the exception of the tarsi, almost completely resemble them, will constitute our second section, that of the Arcuata. In the Cancer, Fabr. Or the Crab properly so called, the third joint of the external foot-jaws is emarginated or marked with a sinus near the internal and almost square extremity. The antennae scarcely extending be- yond the front and composed of but few articulations, are flexed and glabrous, or but slightly hairy. The hands are rounded and have no appearance of a crest on the upper edge. The radical joint of the external antennae is, in some, much larger than the following ones, and resembles a lamina; terminated by a sa- lient and advanced tooth, closing inferiorly the internal corner of the ocular cavities. The fossulae of the middle or internal antennae are nearly longitudinal. Such is the C. pagurus, L.; Crabe poupart, Sec; Herbst., IX, 59. Shell reddish, wide, plane, almost smooth above, with nine festoons in each lateral margin, and three teeth in front. Its claws are large, smooth, with black fingers studded internally with blunt tubercles. It is sometimes a foot wide, and weighs five pounds. Common on the Atlantic coast of France, but less abundant in the Mediterranean. Its flesh is esteemed. Dr. Leach separates it generically from the other Crabs: Malac. Brit., XVII, x. In the others, the lower joints of the Antennae are cylindrical; al- though somewhat larger, the first does not differ from the following (1) See the article Plat yuniquc, Encyc. Methodique. DECAPODA. 27 ones in form or proportion, and does not extend beyond the internal canthus of the ocular fossulae; those of the intermediate antennae are prolonged in a direction rather parallel to the breadth of the shell than to its length. There are some of them C. ll-dentalus. Fab., in which the ex- tremity of the fingers are excavated like the bowl of a spoon: they form the Clorodins, Leach. Several species, where they terminate in a point, are remarkable for the arcuation of the edges of the shell which terminate posteriorly by a fold and overlapping projection, in the manner of an angle.. Those with a tridentated front, and whose shell only presents that projection or posterior tooth, com- pose his genus CarpWus. The species of this subdivision, C. co- rallmus, F. ; C. mauculatus, Id., are marked with round blood- coloured spots. They more particularly inhabit the Indian Ocean. Many fossil Crabs appear to me to belong to this subdivision. The Xantho, of the same, some of which, Xanth. Jloridus, Leach, Malac. Brit., XI; Cancer poressa, Oliv., Zool. Adriat., II, 3, inhabit the coast of France, have their antennae inserted in the internal can- thus of the ocular fossulae, and not in the outer one, as in those just mentioned. Other considerations would authorise us to augment the number of these divisions, but our limits require us merely to indicate the principal ones. The " Crabe vulgaire de nos cules" of the first edition of this work, has in this one been placed among the Portuni. P. masnas. Pirimela, Leach. These Crustacea completely i*esemble Crabs, but their external antennae extend considerably beyond the front, and their stem, longer than their pedicle, consists of numerous joints. The fossulae of the intermediaries, as in the C. pagurus, are rather longitudinal than transversal. But a single species is known, the P. denticulata, Leach, Malac. Brit., VIII; it is found in the British channel and in the Mediterranean. Perhaps we should refer to this species, the fossil described by Desmarest under the name of Alelecycle ru- gueux, in the Hist. Nat. de Crust. Foss., IX, 9. Atelecyclus, Leach(l). Fossulae of the intermediate antennae longitudinal; lateral antennae (1) We had, at first, placed this subgenus, as well as the following one, among the Orbicularia. 28 CRUSTACEA. elongated, salient and composed of many joints, but very hairy as well as the claws; the latter strong, and with compressed hands. The third joint of the foot-jaws sensibly narrowed above, resembling an obtuse or rounded tooth; conical tarsi, and the ocular pedicles of the ordinary size. The tail is longer than in the preceding Crus- tacea. Two species have been described(l). One from the coast of England, of a sub-orbicular form, and the other from that of France, Mediterranean as well as Oceanic. The Thia, Leach, Approaches Atelecyclus in the lateral antennae^in the direction of the fossulae in which the intermediaries are placed, in the form of the third joint of the external foot-jaws, and in the sub-orbicular shell; but the eyes, together with the pedicles, are extremely small and scarcely salient. The tarsi are' strongly compressed and sub- elliptical. The front is arcuated, rounded, and without any marked dentations. The pectoral space between the feet is very narrow, and of the same breadth throughout. The claws are much weaker in proportion. The shell is smooth, and in some respects the Thiae approach the Leucosias and the Corystes. The type(2) of this subgenus, whose habitat was unknown, has been discovered by Milne Edwards in the sandy shores of the Mediterranean, near Naples. Risso Journ. de Phys., 1822, p. 251, described a second, dedicated to M. de Blainville, which he found in the river at Nice. The Mursia, Leach(3), Of which but a single species is known, and which is peculiar to that part of the Ocean which bounds the southern extremity of Afri- ca, approaches the Matutae and several Portuni, in the long spine Avith which each side of the shell is armed posteriorly; it also approximates to the true Crabs in the form of the shell and of the external foot-jaws, with this difference, that their third joint forms an elongated square, harrowed and obliquely truncated at its supe- rior extremity; but, as in the Calappae and Hepati, the hands are strongly compressed above, having a sharp and dentated edge, re- sembling a crest(4). (1) See Conskl. Ge'ner. surlaClasse des Crust, Desmar., p. 88,89. (2) Thiapolita, Leach, Zool. Miscell. ciii. (3) This name must be changed to avoid confounding- the division with that of Nursia, another subgenus. (4) Desmarest, Consid. Gener., &c, IX, 3- DECAPODA. 29 Hepatus, Latr. The Hepati have a considerable affinity with the true Crabs in the widened form of their shell, and the shortness of their lateral anten- nae, approaching the Mursiae and Calappas in their compressed hands, the upper edge of which resembles a crest; but the third joint of their external foot-jaws forms an elongated, narrow, and pointed triangle, without any apparent emargination, a character also ob- served in the Matutas and Leucosias. The species(l) which served as the type of this division was confounded by Fabricius with the Calapp. It is as large as an ordinary Pagarus. The shell is yellowish, dotted with red, and the margins finely and unequally crenulated. The eyes are small and approximated, and the feet are traversed by red bands. Although the tail of the male has but five complete seg- ments, the traces of two others may still be discovered on the sides. This species is common at the Antilles. In our third section or that of the Quadrilatera, the shell is nearly square or heart-shaped, the front generally prolonged, in- flected or much inclined, and forming a sort of clypeus. There are seven segments, distinctly marked across their whole breadth, in the tail of both sexes. The antennas are usually very short. The eyes of most of them are fixed on long or stout pedicles. Several live habitually on land, inhabiting holes excavated by them- selves; others frequent fresh water streams. They move with great swiftness(2). A first division will comprise those in which the fourth joint of the external foot-jaws is inserted at the superior internal extremity of the preceding one, either in a short, truncated projection, or in a sinus of the inner margin. They approach nearest to the Crabs proper. The shell of some is nearly square, or a trapezium, but not trans- verse, or almost in the form of a truncated heart. The ocular pedi- cles are short, and inserted either near the lateral and anterior an- gles of the shell, or more internally, but always at a considerable distance from the middle of the front. Here comes the (1) Hepatus fasciatus, Latr. ; Desmar., Consider., IX, 2; Calappa angustata, Fabr. ; Cancer princeps, Bosc; Herbst., xxxvii, 2. See also his Cancer armadillus, VI, 42, 43. (2) I consider them, with respect to their habits and some of the characters of their organization, as being- the furthest removed from the other Decapoda; they should be placed at one of the extremities of that order- 30 CRUSTACEA. Eriphia, Lat. Where the lateral antennae are inserted between the ocular cavi- ties and the median antennae ; the nearly cordiform shell is truncated posteriorly, and the eyes are removed from its anterior angles. The coast of France furnishes a species Cancer spinifrons, Fab.; Herbst., XI, 65; Desmar., Consider., XIV, 1, which is the Pasurus of Aldrovandus. The sides of its shell are fur- nished with five teeth, the second and third bifid. The front and claws are spiny; the fingers black. Trapezia, Lat. The Trapeziae resemble the Eriphise in the insertion of their late- ral antennae, but their shell is nearly square, depressed, and smooth; the eyes are placed at its anterior angles, and the claws, in compa- rison with the other feet, very large. All the species are exotic(l), and inhabit Eastern Seas. The Pilumnus, Leach, Differs from the two preceding subgenera, in the insertion of the lateral antennae at the internal extremity of the ocular cavities, above the origin of the pedicles of the eyes. The Pilumni, as to the form of the shell, approach nearer to the Crustacea of the second section, than the other Quadrilatera, and in this respect stand some- what ambiguously between the two. As in most of the Arcuata the third joint of their foot-jaw is nearly square or pentagonal. The lateral antennae are longer than the ocular pedicles, and have a seta- ceous stem longer than the peduncle and composed of numerous small joints. The tarsi are simply pilose(2). Thelphusa, Lat. (3) The lateral antennae situated as in the Pilumni, but shorter than the ocular pedicles, composed of but few joints, and with a cylin- drico-conical stem hardly longer than its peduncle. The shell is (1) Cancer cymodoce, 'Herbst., li, 5? C. rufo-pundatus, Id., xlvii, 6; C. glaber- rimus, Id., xx, 115. See the article Trapezie, Encyc. Methodique. (2) Seethe article Pilumne, Encyc. Method., and Desmarest, op.cit. p. 111. (3) The Fotamophiks of the first edition of this work. That name having been already applied to a genus of Coleopterous Insects, I have substituted the present one. See this word in the second edition of the Nouv. Diet. d'Hist. Nat. They are the Potamobias, Leach, Potamon, Savigny. DECAPODA. 31 almost shaped like a truncated heart, and the tarsi are furnished with spinous or dentated ridges. Several species are known, all of which inhabit fresh water, but capable, as it would appear, of living at a distance from it for a considerable time. One of them, mentioned by the an- cients, is found in the south of Europe, the Levant, and in Egypt; it is the Crabe fluviatile, of Belon, Rondelet, and Ges- ner(l). It is very common in several brooks and various lakes of the craters of the south of Italy; its effigy is observable on different antique Grecian medals, particularly on those of Si- cily. The shell is about two inches in each diameter. It is greyish or yellowish, as the animal is living or dead, mostly smooth, with little incised rugae and asperities on the anterior sides. The front is transversal, inclined, reflected, and eden- tated. The claws are rough, with a reddish spot at the extrem- ity of the fingers, which are long, conical, and unequally den- tated. The Greek monks eat it raw, and during lent it forms one of the articles of diet used by the Italians. Two naturalists, travellers of the government, prematurely taken from the sciences, Delande and Leschenault-de-Latour, discover- ed two other species; one was collected by the first in his travels to the south of Africa, and the other by the second in the mountains of Ceylon. The Cancer senex of Fabricius (Herbst., XL, 5), should, in my opinion, be referred to the same subgenus. It inhabits the East Indies. A species peculiar to America, the Thelphusa serrata, Herbst., X, ii, is proportionably wider and flatter than the others, pre- senting certain characters which seem to indicate a particular division(2). Other Quadrilatera having, like the preceding ones, the fourth joint of the external foot-jaws inserted in the internal extremity of the previous joint, differ from them in the trapezoidal, transverse and (1) See Olivier Voy., en Egypte, pi. xxx, 2; and the plates of Nat. Hist, in the great work on that country. (2) See also the subgenus Octpode. I have made a new one called Tmciio- dactylus, with a fresh-water species from Brazil analogous to the preceding ones, but with an almost square shell, the third joint of the external foot-jaws forming an elongated triangle hooked at the end, and the tarsi covered with a close down. The Graspus tesselatus, of the pi. (cccv, 2) of Nat. Hist., Encyc. Method., is also the type of the new genus Melia, but one of too little importance to be treated of in detail in a work like this. 32 CRUSTACEA. widened form of the fore-part of the shell, as well as in their ocular pedicles, which, like those of the Podophthalmi, are long and slen- der, extending to the anterior angles, and inserted near the middle of the front. The claws of the males are long and cylindrical: such is the Gonoplax, Leach. Two species of which are found in European seas; one of them, however, may possibly be a mere variety of the other. The first Cancer angulatus, L.; Herbst., I, 13; Leach, Ma- lac. Brit., XIII, has the anterior angles of its shell prolonged into a point, and a second, but smaller spine behind. Two others are observed on the claws of the males, one on the joint called the arm, and the other on the internal side of the carpus; the hands are elongated, and somewhat narrowed at base; ano- ther tooth is found on the superior extremity of the thighs of the other feet. The body is reddish. It inhabits the western coast of France, and that of England. In the second Cancer rhomboides, L., the shell presents no other spines than those formed by the prolongation of the ante- rior angles. The body is smaller, and of a reddish-white or flesh colour. From the rocky localities of the Mediterranean(l). In the second division of the Quadrilatera, the fourth joint of the external foot jaws, or those which cover the other parts of the mouth below, is inserted in the middle of the extremity of the preceding joint, or more outwardly. Sometimes the shell is trapezoidal or ovoid, or is shaped like a heart truncated posteriorly. The ocular pedicles, inserted at a short , distance from the middle of its anterior margin, extend to its ante- rior angles, or even beyond them. Commencing with those whose shell is transversely quadrilateral, widened before and narrowed behind, or which has the form of an egg, we first observe the Macrophthalmus, Lat. Where the shell, as in the Gonoplaces, is trapezoidal and the claws are long and narrow; the ocular pedicles are slender, elongated, and lodged in a groove under the anterior margin of the shell. The first joint of the intermediate antennae is rather transverse than lon- gitudinal, and the two which terminate them are very distinct and (1) See the article lihombille, Encyc. Methodique. DECAPQDA. 33 of a mean size. The external foot-jaws are approximated inferiorly at their inner edge, leaving no interval between them, and their third joint is transverse. They(l) inhabit the Eastern Ocean and the seas of New Holland. The following, which constitute the subgenera Gelasimus, Ocypode, and Mictyris, inhabit burrows, are remarkable for the celerity of their course, and have the fourth pair of feet, and next to them, the third, longer than the others. The intermediate antennae are excess- ively small and hardly bifid at the extremity; the radical joint is nearly longitudinal. They are peculiar to hot climates. Here the shell is solid, of a quadrilateral or trapezoidal form, widest before. Gelasimus, Lat. Uca, Leach. Eyes terminating their pedicles like a small head; third joint of the external foot-jaws forming a transverse square; last segment of the tail of the males almost semi-circular, that of the females nearly orbicular. The lateral antennae are longer and slenderer in proportion than those of the Ocypodes. One of the claws, now the right, and then the left, varying in individuals of the same species, is much larger than the other; the fingers of the small one are frequently shaped like a spoon or spatula. The animal closes the entrance of its bur- row, which it excavates in the vicinity of the sea-shore, or in marshy places, with its large claw. These burrows are cylindrical, oblique, very deep, and placed close to each other, but are usually inhabited by a single individual. Their habit of holding the large claw in an upright position before the body, as if making an appellative gesture, has obtained for them the name of Calling-Crabs Cancer vocans. One species, observed by Bosc in South Carolina, passes the three winter months in its retreat without leaving it, and only visits the sea when about to spawn(2). (1) Gonoplax transversus, Latr., Encyc. Method., Hist. Nat., ccxcvii, 2; Can- cer brevis, Herbst, lx, 4. The Gonoplace de Latreille, a fossil species described by Desmarest, Hist. Nat. des Crust. Foss., IX, 1 4, and perhaps also his G. incise, IX, 5, 6, may be a Macrophthahnus; generally speaking, however, his fossil Gonoplaces are Gelasimi. The species he calls Gelasime luisante, VIII, 7, 8, does not appear to differ from the living one which I have called the maracoani, Encyc. Method., lb., ccxcvi, 1. (2) See the article Gelasime, Nouv. Diet. d'Hist. Nat, Ed. II, and the same article in the work of Desmarest on animals of that class. The Crabs, cietie-efe, cietie-panama, of Marcgrave, appear to me synonymous with the Gelasimus pugi- lator. According to the observations of M. Marion, communicated to the Acad. Vol. III. E 34 CRUSTACEA. Ocypode, Fabr. Eyes extending into the greater part of the length of their pedicles, or claviform; third joint of the external foot-jaws forming a long square; tail of the males very narrow, and the last joint an elongated triangle; that of the females is oval. The claws are nearly similar, strong, but short, and the forceps shaped like a reversed heart. Agreeably to the indication afforded by their generic name, these Crustacea run with great swiftness, which indeed is such, that a horse can scarcely overtake them, whence the name of Eques, given to them by the older naturalists. They are now sometimes termed Land-Crabs, and occasionally, na- turalists have confounded them with the Gecarcini, under the gene- ral denomination of Tourlouroux. The Ocypodes, during the day, remain in the holes or burrows they have excavated in the sand, near the sea-shore, and quit them after sun-set. Ocyph. eques; Cancer cursor, L. ; Cancer eques, Bel.; Ocyph. ippeus, Oliv., Voy. dans l'Emp. Ottom., II, xxx, 1. Distin- guished from all the others by the bundle of hairs, which termi- nate the ocular pedicles. It inhabits the coast of Syria, that of Africa bordering on the Mediterranean, and is even found at Cape de Verd. In the Ocyp. cerathophthalmus; Cancer cerathopt., Pall., Spic. Zool., fasc. IX, v, 2^8, the superior extremity of these pedicles ex- tends beyond the eyes for more than a third of their whole length, in a conical and simple point. The forceps are codi- form, very rough, and their cutting edge dentated. From the East Indies. In others the pedicles are terminated by the eyes forming a sort of club. Some from the eastern continent and all those of the western world are thus formed, but the latter possess a peculiar cha- racter, which indicates more aquatic habits, or that they swim with more facility: their feet are smoother, flatter, and furnished with a fringe of hairs. Such is the O. blanc, Bosc. Hist. Nat. des Crust., I, 1. The Cumuru of Marcgrave belongs to this division(l). In classing the collection of the Museum d'Histoire Naturelle, we Roy- des Sc, by M. de Blainville, this inequality of the forceps is peculiar to the males, at least such was the case in all the numerous specimens examined by him in his voyage to the East Indies. (1) For the Ocypodes of the western continent, see the observations of M. Say, Journ. Ac. Nat. Sc. Philad. His Ocyp. reticulatus is a Grapsus. Consult, also, the article Ocypode, Nouv. Diet. d'Hist. Nat., and the work of M. Desma- rest. DECAPODA. 35 placed among the Ocypodes, under the specific name of quadriden- tata, a crustaceous animal, which appears to us to bear a close re- semblance to the Gecarcin trois-epines, Desmar., a fossil species, Hist. Nat. des. Crust. Foss., VIII, 10 ; he suspects it may belong to the genus Thelphusa. Here, at least in the females, the shell is very thin, membranous, and flexible, and the body almost round or subovoid. The ocular pedicles are sensibly shorter than in the preceding subgenera. First comes the Mictyris, Lat. Where the body is subovoid, highly inflated, narrower and more obtuse before, and truncated posteriorly; the clypeus considerably di- minished, and its extremity narrowed into a point. The claws form an elbow at the junction of the third and fourth joint, the latter of which is almost as large as the hand; the other feet are long, with angular tarsi. To these essential characters we will add, that the ocular pedicles are curved and crowned with globular eyes; that the external foot-jaws are very ample, and their internal edge hairy, the second joint being very large, and the following one almost semi- circular. Two species are known: one is found in the Australasian Ocean(l), and the other in Egypt(2), where it was observed by M. Savigny. Immediately after these come the Pinnotheres? Lat. Very small Crustacea, which cluing a part of the year, in Novem- ber particularly, inhabit various bivalve shells, chiefly the Mytili and Pinnas. The shell of the females is sub-orbicular, very thin and soft, while that of the males is solid, almost globular and somewhat narrowed into a point before. The feet are of a middling length and the claws straight and formed as usual. The external foot-jaws present but three distinct joints, the first large, transversal, and arcuated, and the second furnished at its internal base with a small appendage. The tail of the female is very ample and covers the whole under part of the body. The ancients believed that they resided with the Mollusca, in (1) Lat, Gener. Crust, et Insect., I, 40; Encyc, Method., Atlas d'Hist. Nat. ccxcvii, 3; Desmar., Consider., XI, 2. This subgenus, and that of Pinnotheres, in the first edition of this work, constituted part of the Orbicularia; but in their nat- ural order they approach the Ocypodes, Gecarcini, &c. (2) Pi. d'Hist. Nat., of the great work on Egypt. 36 CRUSTACEA. whose shells they arc. found, on friendly terms, warning- them of danger and seeking food for them. The inhabitants of certain dis- tricts, at the present day, attribute to their presence the unwhole- some qualities sometimes manifested in the Mytili(l). We now arrive at Crustacea, which, although analogous to those just mentioned in the insertion of their ocular pedicles, are re- moved from them in respect to their shell. It is heart-shaped and truncated posteriorly, elevated, dilated and rounded on the sides near the anterior angles. The ocular pedicles are shorter than those of the preceding subgenera, and do not quite extend to the lateral extremities of the shell. The intermediate antennae are always ter- minated by two very distinct divisions. The inhabitants of the French colonies designate them by various appellations, such as, Tourlouroux, Crabes-peints, Crabes cle terre, and Crabes violets, which may apply to different species, or to varieties from age; no observa- tions worthy of credence have as yet settled this point of nomencla- ture. These animals more particularly inhabit intertropical coun- tries and those which adjoin them. Their habits are a constant source of interest to travellers, but by abstracting from their ac- counts all improbable and doubtful facts, their history will be as follows. The greater portion of their life is passed on land, where they secrete themselves in holes, from which they never issue but at night. Some inhabit cemeteries. Once in the year, about the spawn- ing season, they collect in immense bands and pursue a direct course to the sea, heedless of all obstacles; after depositing their ova, they return much enfeebled. It is sa id that they seal up the mouth of their burrow during the time t\ ie y are casting their shell. When this is effected, and while yet soft, they are called Boursiers, and their flesh is much esteemed, although sometimes poisonous. This quality is attributed to the fruit of the manchineel, which they are supposed, falsely perhaps, to have eaten. In some of them, such as the Uca, Lat, The size of the feet, commencing with those of the second pair, progressively diminishes; they are extremely pilose, and the tarsi simply sulcated without any remarkable spines or dentations. The only species known Cancer uca, L., Herbst., VI, 38, inhabits the marshes of Guiana and of Brazil. In others, the third and fourth pair of feet are longer than the (1) For species see Leach, Make. Podopli. Britt, and Uesmar., Consider. Gene>. sur les Crust.-, 116. DECAPODA. 37 second and fifth; the tarsi are marked with dentated or very spinous ridges. They form two subgenera. Cardisoma, Lat. The four antennas and all the joints of the external foot-jaws exposed; the three first joints of these same foot-jaws straight; the third shorter than the second, emarginated superiorly and nearly cordiform; the first of the lateral antennas almost similar and broad. They are called Crabes blancs at the Antilles, though sometimes they have a yellow shell striped with red(l). Gecarcinus, Leach. The four antennas covered by the clypeus; second and third joints of the external foot-jaws, large, flattened, arcuated, and leaving a space between their inner sides, the last one forming a curvilinear trian- gle, obtuse at the summit; it reaches to the clypeus, and covers the three following ones, or the fourth, fifth, and sixth. The most common species Cancer ruricola,L,., Herbst., Ill, 36, when young, IV, xx, 116; xlix, 1, is of a more or less lively blood-red colour, more or less extended, and sometimes spotted with yellow with a deeply marked impression of the letter H. It is the Crabe violet, and Crabe print of travellers; the name of Tourlourou appears to me to be more peculiarly applied to this species(2). Sometimes the shell is nearly square, subisometrical or not, broader than it is long, flattened, and the front turned down for nearly the whole of its width. The ocular pedicles are short and inserted at the anterior lateral angles. The two ordinary divisions of the intermediate antennae are very distinct. The inner sides of the exterior foot-jaws are separated, leaving an angular space be- tween them; their third joint is almost as long as it is broad. The (1) Cancer cordatus, L.; Cancer carnifex, Herbst., XLI, 1, IV, 37; C. guan- humi, Marcgrave. The tarsi have four ridges; there are two additional ones in the Gecarcini. (2) See the article Tourlourou in the Encyc. Methodique. Messrs Audouin and Edwards have lately communicated to the Acad. Roy. des Sc. , some very curious remarks upon an organ peculiar to these animals, which forms a sort of reservoir capable of containing a certain quantity of water, and placed imme- diately above the branchiae. This accounts for the unusual convexity of the ante- rior sides of their thorax. 38 CRUSTACEA. claws are short and thick, and the other feet very flat; the fourth pair, and then the third are longer than the others; tarsi spinous. Plagusia, Lat. The mediate antennse lodged in two longitudinal and oblique fissures traversing the whole thickness of the middle of the clypeus(l). They are inferior or covered by this part in Grapsus, Lam. Where the shell is somewhat wider before than behind, or at least not narrower, while in the Plagusiae it widens from before back- wards. The Grapsi are found throughout all parts of the globe, but are more particularly abundant in the vicinity of the tropics. They are not seen in Europe beyond 50 of latitude. If I mistake not they are called Ceriques at Martinique. Marcgrave has figured some Brazi- lian species by the names of Aratu, Arahc-pinima (Grapsus cruen- tatus, Lat.) and Carava-una. At Cayenne they are called JRaga- beumba, or soldier. These animals conceal themselves during the day under stones, &c, at the bottom of the sea. I have been informed that some of them even climb up the trees on its shores and hide beneath their bark. The broad and flattened form of their body and feet enables them to support themselves for a moment on the surface of the water; they always walk sideways, sometimes to the right and at others to the left. Certain species inhabit rivers within the bounds of tide water, but most frequently live on their banks or on land. They assemble in great numbers, and when any one appears among them, they hurry to the water with a tremendous noise, caused by striking one claw against the other. Their habits are similar to those of other carnivorous Crustacea(2). G. varius, Lat.; Cancer marmoratus, Fab.; Oliv., Zool., Adr., II, 1; Cancre madre, Rondel.; Herbst., XX, 114. Size middling; nearly square, hardly broader than long; yellowish or livid; greatly elongated above, and marked with numerous fine lines and points of a reddish-brown; four flattened projec- (1) P. depressa, Lat.; Herbst., Ill, 35; P . clavimuna, Lat., Herbst, lix, 3; Desmar., Consider., XIV, 2. The tail appears to me to consist of but four dis- tinct segments. The third, however, presents one or two deep and transverse lines. In the Grapsi there are seven segments, the third of which has an angular dilatation on each side of its base. (2) See Bosc, Hist. Nat des Crust. DECAPODA. 39 uons arranged transversely at the base of the clypeus, and three teeth at the anterior extremity of each lateral edge. The tarsi are spiny. The G. porte-pinccau; Cuv. Regne Anim., IV, xii, 1; Rumph., Mus. X, 2; Desmar., Consider., XV, 1, is remarkable for the numerous, long and blackish hairs with which the superior surfaces of the fingers are furnished. The tarsi are without spines, a character exclusively peculiar to this species. It is found in the East Indies(l). In our fourth section or the Orbiculata(2), the shell is either sub-globular, rhomboidal or ovoid, and always very solid; the ocular pedicles are always short or but slightly elongated; the claws of unequal size according to the sex, those of the males being largest; there are never seven complete segments in the tail; the buccal cavity grows gradually narrower towards its superior extremity, and the third joint of the external foot-jaws always forms an elon- gated triangle. The posterior feet resemble the preceding ones, and neither of the latter is ever very long. In the Corystes, Latr., The shell is an ovoidal oblong, and crustaceous;the lateral antennae are long, projecting and ciliated; ocular pedicles of a mean size and separated; third joint of the external foot-jaws longer than the pre- ceding one, with a visible emargination for the insertion of the next. The tail is composed of seven segments, the two middle ones obli- terated in the males. A species Cancer personatus, Herbst., XII, 71, 72; Leach, Malac. Brit., VI, 1, is known on the coast of France. The lateral edge of its shell is marked with three notches on each side. A second was brought from the Cape of Good Hope by the late Delalande. Leucosia, Fab. Form of the shell varying, but generally ovoid or almost globular, and always very hard and stony; lateral antennae and eyes very small; eyes approximated. The third joint of the external foot-jaws is smaller than the second, and without any apparent internal sinus; (1) See the article Plagusie, Encyc. Method., and the Histoire des Animaux sans vertebres of Delamarck, genus Grapse. (2 ) The Orythia: and the Dorippes, in a natural series, would, in my opinion, belong to this section, and lead to the Corystes; their shell is a truncated ovoid. 40 CRUSTACEA. these parts are contiguous inferiorly along the internal edge, and form an elongated triangle, the extremity of which is received into two upper cells of the buccal cavity. The tail, which is ample and suborbicular in the females, usually consists of from four to five seg- ments, but never seven. Doctor Leach(l) has separated this genus of Fabricius into seve- ral genera, which, however, we will consider as simple divisions. Those species which have a transversal shell, with the middle of its sides greatly prolonged or dilated, so as to resemble a cone or cylinder, form his genus Ixa{2). Those which have a rhomboidal shell with seven conical points, resembling spines on each side, compose that of Iphis. If the shell still has the same rhomboidal figure, but merely pre- sents angles or sinuses on the sides, it becomes his genus Nursia. If these lateral edges are smooth, we have his Ebalia. The Leucosiae with an ovoid or nearly globular shell, and other- wise distinguished from several of the preceding by the claws being always longer than the body and thicker than the other feet, and by the tarsi being sensibly striate, may be divided thus: In some the front projects, or at least is not surpassed by the superior extremity of the buccal cavity. The outer branch of the external foot-jaws is elongated, and almost linear. Here the claws are slender, the hands cylindrical, and the fingers long. Sometimes the shell is nearly globular, and either very spiny, as in the genus Jlrcania, or smooth as in Ilia. At others, the shell is suborbicular and depressed, as in the genus Persephona, or ovoid as in Myra. There the claws are thick, with ovoid hands and short fingers. They constitute the true Leucosise of that naturalist. In the others, the superior extremity of the buccal cavity out- reaches the front. The outer branch of the external foot-jaws is short, and arcuated; the shell rounded and depressed. This last division comprises his genus Phylira. Other considerations, founded on the proportions of the feet and the form of the external foot-jaws, strengthen these characters. The Leucosie noyau; Ilia nucleus, Leach; Cancer nucleus, Lin., Herbst., XI, 14, is common in the Mediterranean; its shell is globular, granulated on the sides and posteriorly; the front is notched; two teeth on the posterior margin, and two others (1) Leach Zool. Misc. Ill; Desmar., Consid. (2) Leucosia cylindrus, Fabr., Herbst., 11,2931. DECAPODA. 41 widely separated on each lateral margin; the posterior largest and spiniform, and situated ahove the origin of the posterior feet. The sea coast of the western departments of France produces some other species which belong to the genus Ebalia, Leach(l). All the remaining ones are from India and America. Some fossil Leucosis are found in the East Indies. Three species have been described by M. Desmarest, two of which, according to him, are true Leucosiae, Leach, and which are now living in the same countries, and peculiar to them. Our fifth section, that of the Thigona, is composed of those spe- cies whose shell is usually triangular or subovoid, narrowed before into a point or kind of beak, generally uneven and rough, with late- ral eyes. The interval comprised between the antennae and the buccal cavity, is always nearly square, as long, or almost as long as broad. The claws, at least those of the males, are always large and elongated. The following feet are very long in a great number, and sometimes the two last even differ in form from the preceding ones. The third joint of the external foot-jaws is always nearly square or hexagonal, in those at least whose feet are of the ordinary length. The apparent number of the caudal segments varies. In both sexes of several it is seven; in others, however, the males at least, it is less. Several of these Crustacea are designated by the vulgar appella- tion of Jlraignees tie mer or Sea-spiders. Although the species of this tribe are very numerous, but two have as yet been discovered except in a fossil state, one of which at least Maia squinaclo exists at the present day in a living state, and in the same localities(2). A first division will comprehend those whose second and follow- ing feet are similar, and which diminish progressively in size. From the latter we will form a first group of all those where the tail, either in both sexes, or in the females alone, is composed of seven segments. The third joint of the external foot-jaws is almost always square, and truncated or notched at the superior internal angle. Very large claws, particularly so when compared with the other feet, which are extremely short, directed horizontally and perpen- dicularly to the axis of the body as far as the carpus or joint im- mediately preceding the hand, then reflected anteriorly on them- (1) Make. Brit., xxv. (2) See Desmar., Hist. Nat. des Crust. Foss Vol. III. F 42 CRUSTACEA. selves with the fingers bent, suddenly forming an angle; very short ocular pedicles, projecting but little, if at all, from their cavities; a stony and very uneven or spiny shell, designate the Parthenope, Fab. The lateral antennae of some are very short, not exceeding the length of the eyes; the first joint is entirely situated under the ocular cavities. If there are seven segments in the tail of both sexes, we have the genus Parthenope properly so called(l) of Leach. If that of the males presents but five, it is his genus Lambrus{2). The lateral antennae of the others are sensibly longer than the eyes; their first joint extends to the superior internal extremity of the cavities peculiar to these latter organs, and appears to be con- founded with the shell. The post-abdomen is always composed of seven segments. The claws of the females are much shorter than those of the opposite sex. The same naturalist distinguishes these Crustacea generically by the name of Eurynoma. But a single spe- cies is known which inhabits the English and French coasts(3). All the other Parthenopes, one excepted(4) are from the Indian Ocean. In the following ones, the claws always project, and their length, at most, is double that of the body; their fingers are not suddenly bent into an angle(5). Here the length of the longest feet the second barely exceeds that of the shell from the eyes to the origin of the tail. The under part of the tarsi is usually either dentated or spiny, or furnished with a ciliated fringe terminated like a club. We will commence with those whose ocular pedicles are very short, or of a mean length, susceptible of being entirely retracted (1) Parthen. horrida, Fab. ;Rumph., Mus., IX, 1; Seba, III, xix,16, 17; Herbst., XIV, 88. (2) Panth. longitnana, Fab.; Rumph., Mus., VIII? P. giraffa, Fab.; Herbst, XIX, 108, 209; P. lar, Fab.; P. rubus, Latr.; Cancer contrarius, Herbst., lx, 3; P. macrocheks, Lat., Herbst., XIX, 107; Cancer longimanus, L., fern., P. trigonomana, Lat.; Cancer prensor, Herbst., xli, 3. (3) Cancer asper, Perm., Brit. Zool., IV; Eurynoma aspera, Leach, Malac. Brit., XVII. (4) Parthenope angulifrons, Latr., Encyc. Method.; Cancer tongimanus, Olivi. (5) The first joint of the lateral antennae appearing to form part of the shell, has been mistaken by several naturalists, the second having been considered by them as the first. DECAPODA. 43 within their cavities, and whose claws, at least in the males, are considerably thicker than the other feet. Mithrax, Leach. Robust claws: ends of the fingers like the bowl of a spoon; stem of the lateral antennae sensibly shorter than the pedicle; the tail composed of seven segments in both sexes. All the known species are from the American seas(l). Acanthonyx, Latr. A tooth or spiniform projection on the inferior side of the tibae; under part of the tarsi pilose, and as if pectinated; superior surface of the shell smooth. The tale of the males presents, at most, but six complete segments(2). Pisa, Leach. Claws of a mean size, with pointed fingers; tibae without any spine beneath, and the tail composed of seven segments in both sexes. As in the preceding subgenera, the lateral antennae are inserted at an equal distance from the fossulae that receive the intermediate ones, and from the ocular cavities, or rather nearer to the latter. These, as in the genus Naxia, Leach, (3) have two ranges of den- tations on the under part of the tarsi. Those have but a single row of dentations, or a simple fringe of thick claviform cilia, under the same joint. The latter constitute the genus Lissa of that author(4). Among those which have a range of dentations, the feet some- times gradually diminish in length, as happens in his Pisa(5) pro- perly so called, and at others, the third ones, in the males, become abruptly shorter than those which precede them, as in his Chori- nus(6). Pericera, Latr. The Pericerae, though approaching the Pisae in the form and pro- (1) Mithrax spinicinctus, Latr.; Desmar., Consid., p. 150; Cancer kispidus, Herbst., XVIII, 100; Cancer aculeatus, Herbst., XIX, 104; C. spinipes, ejusd., XVII, 94. The lachus hircus, Fab., is perhaps a congener. (2) Maia glabra, Collect, du Mus. d'Hist. Nat.; Maia lunulata, Risso, I, 4; Li- binia lunulata, Desmar. (3) Pisa aurita, Latr., Encyc. Method. P. monoceros, lb. (4) Pisa chiragra, Latr., Encyc. Method.; Desmar., Consid. (5) Pisaxyphias, Latr., lb.; ejusd., lb. P. aries,- P. barbicornis; P. corni- gera; P. styx; P. bicornuta; P. trispinosa; P. armata, Leach, Malac. Brit., XVII; Cancer muscosus ? , Lin.; P. tetraodon, Leach, lb. xx. (6) Pisa heros, Latr., Encyc. Method. 44 CRUSTACEA. portions of the claws, and the number of their caudal segments, are removed from them, as well as from the other anterior subgenera, by the insertion of their lateral antennae under the snout, and their approximation to the fossulae lodging the intermediate ones, being closer than to those which receive the ocular pedicles(l). In the two following subgenera the ocular pedicles are short or moderate, as well as in the preceding ones. But the claws, even those of the males, are hardly thicker than the following feet. The tail always consists of seven segments. In the Maia, Leach, The second joint of the lateral antennae seems to arise from the internal canthus of the ocular fossae. The hand and the joint which precedes it are nearly of the same length. The shell is ovoid. This subgenus established by Lamarck, and originally consisting of a great number of species, comprises, at present, according to the method of Dr Leach, but one, the Cancer squinado, Herbst, XIV, 884, 5, lvi; Inachus cornutus, Fab. It is very common on the coast of France and in the Mediterranean, where it is called JLraignec de mer. It is one of the largest of the European Crustacea, and the Maia of the ancient Greeks, figured on some of their coins. They attributed great wisdom to it, and considered it as sensible to the charms of music. Micippe, Leach. The first joint of the lateral antennae curved, dilated at its supe- rior extremity into a transverse and oblique blade, closing the ocular fossae; the ensuing joint inserted under its superior margin. The shell, viewed from above, appears widely truncated before; its an- terior extremity is inclined, and terminates in a sort of clypeus or dentated rostrum(2). The Stenocionops, Leach, Is distinguished from all the other subgenera of this tribe by (1) Maia taurus, Lam.; Cancer cornudo, Herbst., lix, 6. N.B. The genus Jimathia of M. P. Roux, Hist, des Crust, de la Mediterr., &c, liv. I, does not differ from my Pericera it even appears to me to have the same type. The Lithographic plates which accompany this work are distinctly and faithfully executed. (2) Cancer cristatus, L.; Rumph., Mus., VIII, 1, the male. Cancer phy lira, Herbst.. lviii, 4; Desmar. Consider., XX, 2. DECAPODA. 45 long and slender ocular pedicles which protrude from their fossu- lae(l). There, the under surface of the feet presents neither ranges of den- tations nor claviform cilia. Those of the first pairs, at least, are one half longer than the shell, and frequently much longer. The body is usually more abbreviated than in the preceding subgenera, being either nearly globular, or formed like a shortened e^g. A species of this tribe, Maia retvja, Coll. du Jard. du Roi, whose shell is woolly and forms a truncated ovoid, or is obtuse anteriorly; whose strongly curved elongated ocular pedicles are received into fossulse situated under the lateral margin of the shell ; whose carpus is elongated, as in Maia, pre- sents another character which exclusively distinguishes it, viz. the length of the feet seems to augment progressively from the second pair onwards, or at least to differ but little. It is the type of the genus Camposcia, Leach. In the others, as usual, the length of the feet progressively di- minishes from the second pair to the last. In some of them, the ocular pedicles, although much shorter than in the Stenocionops, are always salient, and the third joint of the pedicle of their lateral antennae is as long, or even larger, than the preceding one, the antenna; themselves terminating in a long seta- ceous stem. They approach the Micippes; such is the Halimus, Latr.(2) In those which constitute the two following sub-genera, the ocular pedicles are susceptible of being entirely retracted within their fos- sulse, and are protected posteriorly by a dentiform projection, or angle, of the lateral edges of the shell. The second joint of the pe- duncle of the lateral antennas is much larger than the following one; they are. terminated by a very short stem resembling an elon- gated stylet. Hyas, Leach. Lateral edges of the shell dilated behind the ocular cavities which are large and oval; external side of the second joint of the lateral (1) Cancer cervicornis, Herbst., lviii, 2, from the Isle of France. M. Desmarest was mistaken inciting, as the type, Consid. Gen. sur les Crust, p. 153, the Maia taurus, Lamarck. (2) Two species, one of which appears to be allied to the Cancer super ciliosus, L., Herbst, XIV, 89. 46 CRUSTACEA. antennae compressed and carinated; ocular pedicles, when erected, entirely exposed. The body is sub-ovoid(l). In the Libinia, Leach, The ocular fossulae are very small and nearly orbicular, and the ocular pedicles are very short, and but very slightly exertile. The second joint of the lateral antennae is cylindrical, and not compress- ed, or but very slightly so. The body is nearly globular, or trian- gular. We will unite the Doclsea and the Egeria of Leach, to his Li- BINI.ffi. In his Libiniae, properly so called(2), the claws of the males are thicker than the two following feet and almost as long. The length of the longest does not exceed twice that of the shell. The claws of the male Doclaea(3) are much shorter than the two following feet. The length of the latter is hardly more than once and a half that of the shell, which is nearly globular and always co- vered with a brown or blackish down. In the Egeriae(4) the claws are filiform and the hands much elon- gated and almost linear. The following feet are five or six times longer than the shell. The body is triangular. Having reviewed all the sub-genera of this tribe in which the feet subsequent to the claws are of a similar form, and in which the tail, of the females at least, and most generally in both sexes, is composed of seven complete joints or segments, we now pass to those in which it never consists of more than six. The feet are usually long and filiform, as in the last sub-genera. With the exception of the Lep- topi, these Crustacea are also removed from the preceding by the form of the third joint of the external foot-jaws. It is proportion- ally narrower, and contracted at base, and the ensuing joint appears to be inserted in the middle of its superior margin, or more exter- nally. The following sub-genus differs from those which succeed to it, in the tail of the males, where we only find three segments. The form of the third joint of the external foot-jaws appears to me the same as in the preceding sub-genera. (1) Cancer araneus, L.; Leach, Make. Brit., XXI, A; Herbst., XVII, 59? Hyas coarctata, Leach, lb., xxi, IJ. (2) Libinia canaliculata, Say, Journ. Acad. Nat. Sc. Philad. vol. I, p. 77, iv, 1; L. emarginata, Leach, Zool. Misc., cviii. (3) Doclaca Rissonnii, Leach, Zool. Misc., lxxiv. The Inachus ovis and the T. hybridua, Fab., should be referred to it. (4) Egeria indica, Leach, Zool. Misc., lxiii; Inachus spinifer, Fab. DEC APOD A. 47 Leptopus, Lam. Tail of the females composed of but five segments; the body con- vex and feet very long. But a single species is known which is part of the collection of the Museum d'Histoire Naturelle, where it is called Muia longipes. Doctor Leach proposed to designate this genus by the name of Ste- nopus, a denomination we have not adopted, inasmuch as it is al- ready appropriated to another. That of Leptopus, Lam., is com- posed of several species, which, the above mentioned one ex- cepted, according to the characters here given, must be excluded from it. If we except some species of Hymenosomae in which the tail pre- sents but four, or at most five, distinct segments, that part of the body consists of six in all the following sub-genera, either in both sexes, or in the males. The third joint of the external foot-jaws is sometimes in the form of an inverted triangle or of a posteriorly narrowed oval, and sometimes in that of a heart. The ensuing joint is inserted in the middle of its superior margin, or rather more out- wards than inwards. Some of them, such as the three following sub-genera, approach those of which we have just spoken by the almost isometrical, or at least transversal form of the epistoma. The base of the interme- diate antennae is but a short distance from the superior margin of the buccal cavity. One of these sub-genera is distinguished from the others by the flatness of the shell, and by the superior extremity of the first joint (free in several) of the lateral antennae, which does not extend be- yond that of the ocular pedicles. Such is the Hymenosoma, Leach. The shell is triangular or orbicular(l). The species are gene- rally small and peculiar to the Indian Ocean and coast of Australia. The number of caudal segments varies, but never extends beyond six. In the two following sub-genera, the shell is more or less convex, always triangular and terminated before in a rostrum. The first joint of the lateral antennae, always fixed, forms a ridge or salient line between the fossulae of the intermediate antennae and that of the eyes, and which is prolonged beyond the end of the ocular pedicles. In the (1) Hymenosoma orbicularis, Desmar., Consid., xxvi, 1. 48 CRUSTACEA. Inachus, Fab., The tail is always composed of six segments; all the tarsi are nearly straight, or but slightly arcuated; the ocular pedicles are smooth, susceptible of being concealed within their fossulae, and there is a tooth or spine, at least in the males, at the posterior ex- tremity of the latter cavities. Doctor Leach has considerably re- duced the original extent of this group(l). Ach^eus, Leach. Six segments in the tail, but the four posterior tarsi are arcuated or falciform; the ocular pedicles are always salient and present a tubercle anteriorly(2). Next come those in which the epistoma is longer than it is broad, shaped like an elongated triangle truncated at the apex, and in which the origin of the mediate antennae is separated by a considerable space from the superior margin of the buccal cavity. The ocular pedicles are always salient when the head is triangular and termi- nated in a point more or less bifid or entire. Stenorhynchus, Lam. Macropodia, Leach. Six caudal segments in both sexes; anterior extremity of the shell bifid(3). . Leptopodia, Leach. Five segments in the tail of the male; one more in that of the fe- male. The shell is prolonged anteriorly into a long, entire, and dentated point(4). The latter Trigona differ from the preceding in the dissimilitude of their posterior feet. (1) Cancer dodecos ? L.; Inachus scorpio, Fab. ; Inachus Dorsettensis, Leach, Ma- lac. Brit., xxii, A; Inachus phalangium, Fab.; Inachus dorynchus, Leach, lb., xxii, 7, 8; Inachus leptorinchus, ejusd., lb., xxii, B; Cancer tribulus, L. ? Near the Inachi comes a new genus lately established by M. Guerin, called Eurypode, minutely described and carefully figured, Mem. du Mus. d'Hist. Nat. XVI. It ap- proaches that of Inachus, but the ocular pedicles are always salient; the post-ab- domen is composed of seven completely separate segments in both sexes, and the penultimate joint of the feet, or the metarsus, is inferiorly dilated and compressed. (2) Jlchseus Cranchii, Leach, Malac. Brit, xxi, C. (3) Macropodia tenuirostr is, Leach, Malac. Brit., xxiii, 1 5; Inachus longirostrisP Fab. ; Macrop. phalangium, Leach, lb., xxiii, 6. (4) Inachus Sagittarius, Fab.; Leach, Zool. Misc., lxvii. DECAPODA. 49 Pactolus, Leach. The four or six anterior feet simple, or without forceps. The in- ternal extremity of the penultimate joint of the four posterior ones is prolonged into a tooth, forming with the last joint a forceps or didactyle hand. The form of the shell is that of the Leptopodia:, and the tail presents the same number of segments; but the feet are much shorter; those of the third pair were wanting in the individual which served as the type of this section(l). Lithodes, Lat. The Lithodes, as to the form of the first eight pairs of feet, re- semble the other Trigona; their length, however, seems progressively to increase from the second to the fourth, but the two last are very small, bent, but slightly visible, beardless, and apparently useless. The tail is membranous with three crustaceous and transverse spaces on the sides and another on the end, representing the seg- mentary divisions. The eyes are approximated inferiorly. The ex- ternal foot-jaws are elongated and salient, and the shell is triangu- lar, extremely spinous and terminated anteriorly by a dentated point. These Crustacea are peculiar to the Arctic Seas(2). Our sixth section, that of the Cryptopoda(S) consists of Brachyura remarkable for a vaulted projection of the posterior extremities of their shell under which their feet, the two anterior or the claws ex- cepted, can be completely retracted and concealed. The shell is nearly semi-circular or triangular. The superior edge of the forceps is more or less elevated and notched in the manner of a crest. In those species where they are largest, they cover the anterior part of their body, and hence the name of Coq de mer (Sea Cock), and Crabe hontenx (Bashful Crab), which have been given to some of them. One sub-genus of this section, that of JEthra being closely allied by other characters with the Parthenopes of Fabricius, the first sub-genus of the preceding section, it follows, in a natural order (1) Pactolus Boscii, Leach, Zool. Misc., lxviii. (2) Cancer maja. L.; Parthenope rnaja, Fab.; Inachus maja, Id.; Lithodes arc- tica, Leach, Malac. Brit., xxiv. See also the Maja camptschensis, Tiles., Mem. Acad. St. Petersb., 1812, V, VI. (3) Several of the Arcuata, such as the Hepati, Mul'siae, Matutse, among the swimmers, have a crested forceps, and seem to be naturally allied to the Crypto- poda, so that this section should be placed higher in the scale. The same obser- vation applies to the last one, or that of the Notopoda, for some of them approach the Arcuata, and others the Orbiculata and the Trigona. Vol. III. G 50 CRUSTACEA. the Cryptopoda should be placed between the Orbiculata and the Trigona. Calappa, Fabr. An extremely convex shell; the forceps triangular, strongly com- pressed, dentated superiorly like a crest, and perpendicularly cover- ing the anterior part of the body, during the contraction of the feet. The third joint of the external foot-jaws is terminated like a hook, and the superior extremity of the buccal cavity is contracted and divided longitudinally into two cells by a septum. n most of them, the two posterior and lateral dilatations of the shell are incised and dentated. One species, the Calappe migrane, Cancer gramdatus, L.j Calappa gramdata, Fab.; Herbst., XIII, 75, 76, vulgarly styled Con de mer and Crabe honteux, is found in the Mediterranean. The shell is reddish and marked with two deep sulci, and une- qual tubercles of a carmine red. That portion of the lateral margin which precedes the posterior dilatations, is at first nearly entire, and terminates by four very short teeth, the two first being most strongly marked; those of the edges of the dilatations are large, and six in number, two on the posterior margin, and the others lateral. There are two others on the front. The forceps are also furnished with red tubercles, and their crest is formed by seven teeth, the superior of which are acute(l). The others, such as the C. voute Cancer calappa, L.; Calappa fomicata, Fab.; Herbst., XII, 73, 74, have the marginal dila- tations of the shell entire. This species inhabits the seas in the vicinity of Australia and the Moluccas. iETHRA, Leach. The iEthrae differ from the Calappse in their very flat shell, in their forceps, which are not raised perpendicularly, and which do not overshadow the forepart of their body, and in the almost square form of the third joint of the external foot-jaws. (1) In this division come the following- species of Fabricius: C. tuberculata, Herbst, XIII, 78; Iviii, V.C. lophos, Herbst., XIII, 77; C. cristatus, Herbst, xl, 3; C. marmoratus, Herbst., xl, 2. The Guaja apara, Pison and Marcgr., should probably be referred to this species, and according- to the citation ofBarere is the Crabe des paletuviers of the colonists of Cayenne. The Cancer hepaticus of Linnaeus is also a Calappa. DECAPODA. 51 Sometimes(l) the shell is a transversal oval, and at others(2) forms a short and very wide triangle laterally dilated and rounded. The claws are but slightly elongated, and are tolerably thick; here they are longer, angular, and remind us, as does also the form of the shell, of the Parthenopes. These latter species might constitute a sepa- rate subgenus. Finally, our last and seventh division, that of the Notopoda, con- sists of Brachyura, whose last four or two feet are inserted above the level of the others, or which appear to be dorsal and look up- wards. In those where they terminate by a sharp hook, they are usually employed by the animal in seizing various bodies, such as shells, Alcyonii, &c, with which it covers itself. The tail consists of seven segments in both sexes. The tail of some of them, as in other Brachyura, is folded under, and their feet terminate in a sharp hook and are not fitted for nata- tion. Here the shell is nearly square, and terminates anteriorly in an advancing and dentated point, or it is sub-ovoid or truncated before. In the Homola, Leach, The eyes are supported by long pedicles closely approximated at base, and inserted under the middle of the front. The two posterior feet are alone turned up. The claws are larger in the males than in the females. The shell is extremely spinous, with a dentated projection on the middle of the front. The superior foot-jaws are elongated and sa- lient. These Crustacea inhabit the Mediterranean, and were designated by Aldrovandus under the name of Hippo car cini; they are the Thel- xiopes of Rafinesque. Some of the species attain a great size(3). Dorippe, Fab. The eyes widely separated and placed at the anterior and lateral angles of the shell; the four posterior feet turned up; the claws short (1) JEihra depressa, Lam., Hist, des Anim. sans Verteb.; Cancer scruposus, L.; Cancer polynome, Herbst, liii, 4, 5; Desmar., Consid., X, 2. (2) Partlienope fornicata, Fab. (3) Homola spimfrons,l. In the remaining Stomapoda of this family the shell is almost membranous and diaphanous, covers the whole thorax, is curved la- terally beneath, prolonged anteriorly into a spine or ensiform blade, and projects above the base of the mediate antennas and of the eyes. This base or support is susceptible of being curved under and en- closed in the case formed by the curvature of the shield. The pos- terior fins are concealed under the last segment. These very small, soft Crustacea are peculiar to the Atlantic Ocean and the Eastern seas. The fingers of the large claws have no teeth; the second joint of the ocular pedicles is much larger than the first, and has the figure of a reversed cone; the eyes properly so called are large and almost globular; the fin-like appendage of the feet resembles that of the Squillas and Gonodactyli. In the Erichthus, Latr. Smerdis, Leach, The first joint of the ocular pedicles is much shorter than the second; the middle of the lateral edges of the shield has a strongly (1) For the other species, see the article Squille, and pi., of the Encyc. Method.; Desmar., Consid. In pi. XLII, he has given a detailed figure of the Squille queue-rude. (2) Squilla scyttarus, Fab.; Rumph., Mus., Ill, F;Squilla chiragra, Fab.; Desmar. Consid., XLIII. See the article Squille, of the Encyclopedia Metho- dique. (3) See Encyclop. IVfethod., art. Squille. Squilla euseUa? R'issq. 84 CRUSTACEA. angular dilatation, and their posterior extremity exhibits two teeth(l). In Alima, Leach, The first joint of the ocular pedicles is slender, cylindrical, and much longer than the following one: the body is narrower and more elongated than that of an Erichthus; the lateral borders of the shield are nearly straight or are but slightly dilated; there is a slight longitudinal carina on its middle, and each of its angles forms a spine, the two posterior of which are the largest(2). FAMILY II. BIPELTATA. In this family we find the shell divided into two shields, the anterior of which, very large and more or less oval, forms the head, and the posterior, corresponding to the thorax transverse and angular in its circumference, supports the foot- jaws and feet. These latter, with the exception at most of the two posterior and two last foot-jaws, are slender and fili- form, usually very long and accompanied by a lateral, ciliated appendage. The other four foot-jaws are very small and conical. The base of the lateral antennae exhibits no scale ; the intermediaries are terminated by two threads. The ocu- lar pedicles are long. The body is much flattened, mem- branous, and diaphanous ; the abdomen small and its posterior fin without spines. It comprises but a single genus, the 9 Phyllosoma, Leach, Of which all the species inhabit the Atlantic Ocean and Oriental seas(3). (1) Erichthus vitreus, Lat. See art. Squille, Atl. d'Hist. Nat. of the Encyclop. Method., pi. cccliv; and Desmar. Consid., XLIV, 2, 3. (2) Alima hyalina, Lat., Encyclop. Method., art. Squille, and Ibid. Atl. d'Hist. Nat., CCCLIV, 8; Desmar., Consid., XLIV, 1. (3) See Encyclop. Method., and Nouv. Diet. d'Hist. Nat., Ed. II, article Phyl- losome,- also the work of Desmarest on the Crustacea and the Zoology of the Voy. de Freycinet. As respects their nervous system, the Phyllosoma: seem to be in- termediate between the preceding and subsequent Crustacea. See Audouin and Edwards, op. cit. CRUSTACEA. 85 MALACOSTRACA. b. Eyes sessile and immovable. The Branchiopoda are the only Crustacea of which we shall henceforward have occasion to speak, that exhibit eyes placed on pedicles. But independently of the fact that these pedi- cles are neither articulated nor lodged in special cavities, the Branchiopoda have no shell and are otherwise removed from the preceding Crustacea by various characters. All the Ma- lacostraca of this division are also deprived of a shell ; their body, from the head downwards, is composed of a suite of articulations of which each of the first seven is furnished with a pair of feet, the following and last ones, seven at most, forming a sort of tail terminated by fins or styliform appen- dages. The head presents four antennae, the two interme- diate superior, two eyes, and a mouth composed of two man- dibles, a tongue, two pairs of jaws, and a sort of lip formed by two foot-jaws that correspond to the two superior ones of the Decapoda ; here, as in the Stomapoda, the flagrum no longer exists. The four last foot-jaws are transformed into feet, sometimes simple and at others constituting a claw, but almost always with a single toe or hook. According to the observations of Messrs Audouin and Ed- wards, the two ganglionary cords of the spinal marrow are perfectly symmetrical and distinct throughout the whole of their length, and from those of the Baron Cuvier it would ap- pear that the Onisci are only removed from them because these cords do not present the same uniformity in all the seg- ments of the body, and because there are some ganglions less(l). Thus, according to them, the nervous system of the Crustacea is the simplest of all ; in the Cymothoae and Idoteae the two ganglionary chains are no longer distinct, and those __ _^ (1) See Oniscus. 86 CRUSTACEA. ganglions which immediately follow the two cephalics, form as many small circular masses situated on the median line of the body; but the cords of communication w.hich serve to connect them, remain isolated and attached to each other. It would appear from these facts that the latter Crustacea are higher in the animal scale than the preceding ones, but other considerations seem to us to require a considerable separation between the Talitri and Onisci, and the arrangement of the CymothotC and Idotese in an intermediate rank. The organs of generation are situated inferiorly near the origin of the tail. The two first appendages with which it is furnished beneath, and which are analogous to those presented to us by the same part in the preceding Crustacea, but more diversified, and always, as it appears, supporting the bran- chiae, differ in this respect, according to the sex. The coitus takes place like that of insects, the male placing himself on the back of his female ; the latter carries her ova under the thorax, between scales which form a sort of pouch. There they are developed, and the young remain attached to the feet or other parts of the body of their mother, until they have ac- quired the strength requisite for natation, and providing for their wants. All these Crustacea are small, and mostly in- habit the sea-coast or fresh water. Some are terrestrial, and others are known which are parasitical. They are divided into three orders : those whose mandibles are furnished with a palpus, appear to be naturally connected with the preceding Crustacea such are the Amphipoda ; those in which these organs are deprived of them will consti- tute the two following orders the Lsemodipoda and the Iso- poda. The Cyami, a genus of the second one, being parasi- tical, naturally lead us to the Bopyri and Cymothoae, with which we commence the Isopoda. AMPHIPODA. 87 ORDER III. AMPHIPODA. The Amphipoda are the only Malacostraca with sessile and immovable eyes, whose mandibles, like those of the preceding Crustacea, are furnished with a palpus, and the only ones whose subcaudal appendages, always very apparent, by their narrow and elongated form, their articulations, bifur- cations, and other incisures, as well as by the hairs or cilia with which they are provided, resemble false- or natatory feet. In the Malacostraca of the following orders, these appendages have the form of laminae or scales ; here these hairs and cilia appear to constitute the branchiae. Many of them, like the Stomapoda and the Laemodipoda, have vesicular bursas either between their feet or at their external base, the use of which is unknown. The first pair of feet, or that which corresponds to the se- cond foot-jaws, is always annexed to a particular segment, the first after the head. The antennae, which, with a single ex- ception the Phronimse, are four in number, project, gra- dually taper into a point, and consist, as in the preceding Crustacea, of a peduncle and a single stem, or one furnished at most with a little lateral branch, and usually composed of several joints. The body is generally compressed and curved beneath posteriorly. The terminal appendages of the tail are most frequently styliform and articulated. Most of them swim and leap with facility and always laterally. Some in- habit springs and rivulets, and are often found in couples consisting of the two sexes ; most of them however live in salt water. Their colour is uniform, verging on reddish or green- ish. They may all be comprised in a single genus, that of Gammarus, Fab., Which we may subdivide, in the first place, into three sections, from the form and number of* the feet. 88 CRUSTACEA. 1. Those which have fourteen feet all terminated by a hook, or in a point. 2. Those which also have fourteen feet, but which are the four last at least simply natatory. 3. Those which have only ten apparent feet. The first section is divided into two. Some of them, the Uropteua, Latr., usually have a large head; the antennae are frequently short, and in some but two in number; the body is soft. All the feet, the fifth pair at most excepted, are simple, the anterior are short or small, and the tail is either fur- nished at the extremity with lateral fins, or is terminated by points or appendages, widened and bidentated, or forked at their posterior extremity. They inhabit the bodies of various Acephala or Lin- naean Medusae, and of some other Zoophytes. Here, as in Phronima, Lat., There are but two very short and biarticulated antennae; the fifth pair of feet is the largest of all and terminates in a didactyle forceps; the six appendages of the extremity of the tail are styli- form, elongated and forked or bidentated at the end; six vesicu- lar sacs may be observed between the last feet. Several species ap- pear to exist, but they have not been strictly and comparatively de- scribed. That which has been taken for our type is the Cancel' seden- tarius, Forsk. , Faun. Arab., p. 95; Latr., Gener. Crust, et In- sect. I, ii, 2, 3, which is found in the Mediterranean, and in- habits a membranous transparent body that has the figure of a cask, and which appears to proceed from the body of a species of Beroe. The Phronime sentinelle, Risso, Crust., II, 3, inhabits the in- terior of Medusae, constituting the genera Equoree and Ge'ro- nie of Peron and Lesueur. Another species, according to Leach, has been observed on the coast of Zealand. There we observe four antennae; all the feet are simple; on each side of the extremity of the tail is a lamellated or foliaceous fin, the leaflets of which are acuminated or unidentated at the end. , Hyperia, Lat. The body thickest anteriorly; the greater portion of the head oc- cupied by oblong eyes somewhat emarginated on the inner edge; AMPH1P0DA. 89 two of the antennae, at least half as long as the body and terminated by a long setaceous stem composed of several small joints(l). Phrosine, Risso. Form of the body and that of the head similar to the Hyperiae, but the antennae, at most, the length of the latter, composed of but few and styliform joints, or terminated by a stem resembling an elon- gated cone(2 \ Dactylocera, Lat. The body not thickened anteriorly; the head moderate, depressed, nearly square; eyes small ; four extremely short antennae composed of but few joints, as in Phrosine, of various forms the inferior being thin and styliform, and the superior terminated by a small concave plate on the inner side 'esemble a spoon or forceps(3). The others Gammarin^e, Latr. always have four antennae ; their body, invested with coriaceous and elastic tegments, is generally compressed and arcuated ; the posterior extremity of the tail is de- prived of fins ; its appendages are styliform and cylindrical, or coni- (1) Cancer monoculoides, Montag., Trans. Lin. Soc. XI, ii, 3; Hypirie de Le- sueur, Lat.,.Encyclop. Method., Atl. d'Hist. Nat, CCCXXVIII, 17, 18; Desmar. Consid., p. 258. N.B. Near the Hyperiae should be placed the genus Tuemisto, Lat., carefully figured and described in the Mem. de la Soc. d'Hist. Nat., tome IV. As in the Hyperise, the eyes are very large and occupy the larger portion of the head; two of the antennae (the inferior), all terminated by a multi-articulated stem tapering to a point, are evidently longer than the others. The part there called levre inferieure, is the ligula; those which appeared to form the third pair of jaws are the first of the foot-jaws, and, as in the Amphipodaand Isopoda, close the mouth inferiorly under the form of a lip. The four remaining foot-jaws are very short, directed forwards and laid upon the mouth in such a way that they seem to constitute a part of it, so that if we do not count them, or if we merely consider the following locomotive and much more apparent organs as feet, this animal, like the Hyperia and Phrosine, appears at the first glance to have but ten feet instead of fourteen. The third pair of foot-jaws is terminated by a small didactyle forceps. The same pair of feet, properly so called, is much longer than the others; its penultimate joint is greatly elongated, and is armed with a range of small spines forming a sort of comb. But a single species is known. (2j Phros. macrophthalma, Risso, Journ. de Phys., Octob. 1822; Desmar., lb., p. 259; Cancer galba, Montag., Trans., Lin. Soc, XI, ii, 2. (3) Phros. seminulata, Risso, lb.; Desmar., lb. The stem of the inferior antennae consists of two or three joints, while in Phrosine it is inarticulate. There also, the joints of the peduncles of the same antennae are shorter. Vol. Ill M 90 CRUSTACEA. cal. At least two of their four anterior feet are usually terminated by a forceps. The vesicular bursae, in those where they have been observed the Gammarinae,Latr. are situated at the exterior base of the feet, commencing with the second pair, and are accompanied by a small plate. The pectoral scales which enclose the ova are six in number. Sometimes the four antennae, although of different proportions in several, have a similar form and uses; the inferior have no resem- blance to feet nor do they perform their functions. A subgenus which we have established under the denomination of Ione, Lat., Only, however, from a figure given by Montagu Oniscus thora- cicus, Trans. Lin. Soc. ,IX, III, 3, 4 exhibits very peculiar charac- ters which separate it from all others of the same order. The body consists of about fifteen joints, but only distinguished by lateral tooth-like incisions. The four antennas are very short; those that are external, being longer than the others, are the only ones visible when the animal is seen on its back. Each of the two first segments of the body of the female is provided with two elongated, fleshy, flattened cirri resembling oars. The feet are very short, concealed under the body and hooked. The six last segments are furnished with lateral, fleshy, elongated, fasciculated appendages, which are simple in the male and like oars in the female. At the posterior extremity of the body we also observe six simple, recurved appen- dages, two of which are larger than the others. The abdominal valves are very large, cover the whole inferior surface of the body, and form a sort of receptacle for the ova. This animal remains concealed under the shell of the Calinassa subterranea, on the side of which it forms a tumour. Montagu, having withdrawn one of these Crustacea from its domicil, kept it alive for several days. The female is always accompanied by the male, who fixes himself firmly to her abdominal appendages by means of his forceps. It is a rare animal which, in its habits, approaches the Bopyri(l). All the ensuing Amphipoda have the segments of the body per- fectly distinct, throughout their whole extent; in neither sex nor in any of the species do we find those long oar-like cirri observed in the first of the Iones. (1) See Ann. des Sc. Nat., Decemb. 1826, XLIX, 10, the male II, the fe- male. AMPHIPODA. 91 In the latter, when it exists, the movable toe of the foot, termi- nated by a forceps, is formed of a single joint. Of these last, there are some whose superior antennae are much shorter than the inferior, and even than their peduncle; the stem of the latter is composed of numerous joints. Orchestia, Leach. The second feet of the male terminated by a large forceps, the movable toe long and somewhat curved; those of the female by two toes. The third joint of the inferior antennae is at most twice the length of that of the preceding ones(l). Taliprus, Lat. Neither of the feet forming a forceps. The third joint of the in- ferior antennae more than twice the length of that of the preceding ones; the antennae large and spinous(2). In the following, the superior antennae are never much shorter than the inferior. Some of them, furnished with elongated setaceous antennae ter- minated by a pluri-articulated stem, and without any remarkable forceps, approach the preceding in their superior antennae, which are somewhat shorter than the inferior, and are removed from those that follow by the form of their head which is narrowed before into a kind of snout. Such is Atylus, Leach(3). All those which succeed have the superior antennae as long as the inferior, or longer; their head is not elongated into a snout. Here, as in the five following genera of Leach, the peduncle of the antennae is formed of three joints(4). Some, in their superior antennae, present a character which is (1) Oniscus gammarellus, Pall., Spic. Zool., Fascia, IX, iv, 8; Cancer gamma- rus littoreus, Montag 1 . ; Desmar., Consid., p. 261, XLV, 3. (2) Oniscus locusta, Pall., Spic. Zool., Fascic. IX, iv, 7; Cancer gammarus salta- tor, Montag - .; Desmar., Consid., XLV, 1.1. (3) Atylus carinatus, Leach, Zool. Misc., LXIX; Desmar., Consid., p. 262, XLV, 4; Gammarus carinatus, Fab.; G. nugax? ejusd. ; Phipps, Voy. to the North Pole, XII, 2? (4) The third joint of the peduncle may be very small and thus become assi- milated to the following, or those of the stem; this peduncle, as in the Dexamines, then appears to consist of but two joints. According- to the system of Leach the stem is understood to form another but compound joint. 92 CRUSTACEA. unique in this order the internal extremity of the third joint of the peduncle is provided with a little articulated thread. It distin- guishes the Gammarus, Lat., Where the four anterior feet have the form of small forceps, the movable toe folding beneath. The species best known and the type of this subgenus is the Cancer pulex, L.; Squillu pulex, De Geer, Insect., VII, xxxiii, 1,2. It inhabits brooks, etc. The other species are marine(l). The antennae of the following, as in all the other Amphipoda, are simple or without appendages. Melita, Leach. The second pair of feet, in the male, terminated by a large com- pressed forceps, the toe folding under its internal surface; the an- tennae nearly equal in length; a small foliaceous appendage on each side of the posterior extremity of the body(2). MiERA, Leach. The second feet in the males terminated as in the Melitae, but the toe folds under the inferior edge of the forceps and is not concealed. The superior antennae are longer than the inferior, and the foliace- ous appendages of the posterior extremity of the body are want- ing(3). Amphithoe, Leach. The four anterior feet nearly similar in both sexes; the penultimate article or hand proper, ovoid(4). Pherusa, Leach. The Pherusae only differ from the preceding subgenus in the hand of the forceps, which is filiform(5). There, the peduncle of the antennae is only composed of two joints, (1) See Desmar., Consid., p. 265, 267. (2) Cancer palmatus, Montag., Trans., Lin. Soc, VII, p. 69; Encyclop. Method., Atl. d'Hist. Nat., CCCXXXVI, 31; Desmar., Consid., XLV, 7. (3) Cancer gammarus grosimanus, Montag., Trans. Lin. Soc, IX, iv, 5; Desmar. Consid. p. 264. (4) Cancer rubricatus, Montag., Trans. Lin. Soc, IX, p. 99; Encyclop. Method., Atl. d'Hist. Nat., CCCXXXVI, 33; Desmar., Consid., XLV, 9;0niscus cancellus, Pall., Spic. Zool. Fascic, IX, iii, 18; Gammarus cancellus, Fab. (5) Pherusa fusicola, Leach; Trans. Lin. Soc, XI, p. 360; Desmar., Consid., p. 268. AMPHIPODA. 93 the third being so small as to be confounded with those of the stem, or forming; that of the base ; the superior are longer than the infe- rior. All the feet are simple, or without forceps. Such is Dexamine, Leach(l). In those, the movable toe of the two forceps is bi-articulated. The antennae are of equal length. Leucothoe, Leach. The antennae short, their peduncle formed of two joints; the four anterior feet terminated in a stout forceps; toes of the two first bi-ar- ticulated; those of the second pair consisting of a single and long joint(2). Cerapus, Say. Large antennae, the peduncle consisting of three the superior or four the inferior joints; the two anterior feet small, with a uni-articulated toe; the two following terminating in a large triangu- lar, smooth, dentated hand, with a bi-articulated finger. Ceraphus tubularis, Say, Journ. Acad. Nat. Sc. of Philad., I, iv, 7 11; Desmar., Consid., XLVI, 2. It inhabits a little cy- lindrical tube, and in this respect approaches the subsequent subgenus. Very common at Egg Harbour, New Jersey, among the Sertulariae on which it appears to feed. Finally, the inferior antennae, sometimes much larger than the superior, their stem consisting at most of four joints, have the form of feet, and appear to serve, at least occasionally, as organs of pre- hension. Kere the second feet are terminated by a large forceps. Podocerus, Leach. Eyes very prominent(3). Jassa, Leach. Eyes not prominent(4). There, neither of the feet is terminated by a large forceps. (1) Cancer gammarus spinosus, Montag. , Trans. Lin. Soc, XI, p, 3; Desmar., Consid , XLV, 6. (2) Cancer articulosus, Montag., Trans. Lin. Soc. VII, 6; Desmar., Consid., p. 263, XLV, 5. (3) Podocerus variegatus, Leach, Trans. Lin. Soc, XI, p. 361; Desmar., Consid. p. 269. (4) Jassa pulehella, Leach, lb., p. 361; Desmar., Consid., p. 269. 94 CRUSTACEA. Corophium, Lat. C. longicornis; Cancer grossipes, L.; Gammarus longicornis, Fab. j Oniscus volutator, Pall., Spic. Zool., Fascic. IX, iv, 9; Desmar., Consid., XLVI, 1, called Pernys, on the coast of Ro- chelle, lives in holes, which it forms in the mud, that is covered with hurdles, called bouchots, by the inhabitants- The animal does not make its appearance till the beginning of May. It wages everlasting war against the Nereides, Amphinoma?, Arenicolse, and other marine Annelides, which inhabit the same locality. A curious spectacle is presented by these Crustacea, when the tide is coming in; myriads of them may then be seen moving in every direction, beating the mud with their great arms, and diluting it in order to discover their prey is it one of the above men- tioned Annelides they have discovered, which is ten or twenty times larger than themselves? they unite to attack and devour it. The carnage never ceases until the mud has been thorough- ly turned up and its inequalities levelled. They do not even spare Molluscae, Fishes, or dead bodies on the shore. They mount upon the hurdles which contain Muscles, and fishermen assert that they will cut the threads that keep them there, in order to precipitate them into the mud, where they may devour them at their leisure. They appear to breed during the whole summer, as females carrying their ova are to be met with at various periods. Waders and different Fishes prey upon them. For these interesting observations we are indebted to M. D'Or- bigny, Senior, conservator of the Rochelle Museum and cor- responding member of that of Paris(l). The second section Heteropa, Lat. is composed of those with fourteen feet, the last four of which, at least, are unarmed and des- tined for natation only. It comprises two subgenera(2). Pterygocera, Latr. The thorax divided into several segments; four antennas furnished with setae or hairs in bunches; all the feet natatory and the last large (1) See Encyclop. Method., article Podocere. (2) This and the following 1 section, in the first edition of the Regne Animal, form the second of the Isopoda, that of the Phytibranckiata. But independently of our having 1 discovered mandibular palpi in some of these Crustacea, the form of the subcaudal appendages appears to us to approximate them much nearer to the Amphipoda, than to the Isopoda. We may also observe that these animals, of which we have seen but very few, have not yet been well studied. AMPHIPODA. 95 and pinnated(l); cylindrical, articulated appendages to the posterior extremity of the body. Apseudes, Leach. Eupheus, Risso. The thorax also divided into several segments, but the two ante- rior feet terminated by a didactyle forceps; the two following ones claviform, ending in a point and dentated on the edges; the next six slender and unguiculated at the extremity; the last four natatory. The antennae are simple. The body is narrow, elongated, and has two long setaceous appendages at its posterior extremity(2). The third and last section Decempedes, Lat. is composed of Amphipoda, which present but six distinct feet. Typhis, Risso. But two very small antennae, the head large and eyes not promi- nent; each pair of feet annexed to its peculiar segment, and the four anterior terminated by a didactyle forceps. On each side of the thorax are two movable plates, forming a sort of lids or valves, which when joined, the animal folding up its feet and tail beneath, enclose the body inferiorly and give it a spheroidal appearance. The posterior extremity of the tail has no appendage(3). Anceus, Risso. Gnathia, Leach. The thorax divided into as many segments as there are pairs of feet, but all the latter simple and monodactyle; four setaceous an- tenna; a stout square head with two large projections in the form of mandibles; extremity of the tail furnished with foliaceous fin-like appendages(4). (1) According 1 to the figure of Slabber Oniscus arenarius, Encyclop. Method., Atl. d'Hist. Nat, CCCXXX, 3, 4, the number of feet is but eight; reasoning from analogy, I presume it to be fourteen; besides, if the figure be exact, this genus would belong to the next section. (2) Eupheus ligioides, Risso, Crust., Ill, 37; Desmar., Consid., 285; Apseudes talpa, Leach; Cancer gammarus talpa, Montag., Trans. Lin. Soc, IX, iv, 6; Des- mar, Consid.; XLVI, 9. See the Gammarus heteroclitus, Viviani, Phosphor. Maris, II, ii, 12. N.B. The genus Rhcea, M. Edwards, Ann. des Sc. Nat. XIII, xiii, A, 292, dif- fers from the preceding in the superior antennae, which are stouter, longer, and bifid. (3) Typhis ovoides, Risso, Crust., IF, 9; Desmar., Consid., p. 281, XLVI, 5. (4) Anceus forficularis, Risso, Crust., II, 10; Desmar., Consid., XLVI, 6; An- ceus maxillaris; Cancer maxillaris, Montag., Trans. Lin. Soc, VII, vi, 2; Desmar. lb., XLVI, 7. 96 CRUSTACEA. Praniza, Leach. Four setaceous antennae, as in the preceding; but the thorax viewed from above presents but three segments, the two first of which are very short and transverse, each supporting a pair of feet, while the third, much larger and longitudinal, supports the others. The feet are simple; the head is triangular, pointed before, and has prominent eyes. Each side of the posterior extremity of the body is also pro- vided with a fin(l). Various genera of Messrs Savigny, Rafinesque and Say(2), but the characters of which have not been described or sufficiently de- veloped, appear to belong to this order of the Amphipoda. Even some of the subgenera I have just quoted, require to be re-examined. M. Milne Edwards has made several valuable and detailed obser- vations on several of these Crustacea, which will most certainly tend to elucidate the subject. ORDER IV. LiEMODIPODA. The Laemodipoda are the only Malacostraca with sessile eyes, in which the posterior extremity of the body exhibits no distinct branchiae, and which are almost deprived of a tail, the two last feet being inserted in that extremity, or the seg- ment which connects them with it being merely followed by one or two very small joints. They are also the only ones in which the two anterior feet, that correspond to the second foot-jaws, form part of the head. They all have four setaceous antennas supported by a triar- (1) Oniscus coeruleatus, Montag., Trans. Lin. Soc, XI, iv, 2; Encyclop. Method., Atl. d'Hist. Nat., CCCXXIX, 28, and CCCXXIX, 24, 25; Desmar. Consid., XLVI, 8. (2) I can say nothing of the G. ergine, Risso: the number of its feet would seem to place it in the last section of the Amphipoda; while the manner in which they terminate, and the number of the segments of the body, appear to throw it among the Isopoda. LiEMODlPODA. 97 ticulated peduncle, mandibles, without palpi, a vesicular body at the base of at least the four pairs of feet, beginning at the second or third pair, those of the head included. The body, usually filiform or linear, is composed of eight or nine seg- ments, including the head, and some small appendages in the form of tubercles at its posterior and inferior extremity. The feet are terminated by a stout hook. The four anterior, the second of which are the largest, are always terminated by a moupdactyle forceps or a claw. In several, the four follow- ing ones are shortened, less articulated, without the terminal hook, or are rudimental, and nowise adapted for the ordinary uses of similar parts. The females carry their ova under the second and third segments of the body in a pouch formed of approximated scales. They are all marine Crustacea. M. Savigni considers them as allied to the Pycnogonides, and constituting with the latter the transition from the Crustacea to the Arachnides. In the first edition of this work they formed the first section of the Isopoda, that of the Cistibranchiata. We may unite them in a single genus which, by the law of priority, should be called the Cyamus, Lat. Some the Filiforma, Lat. have a long and very slender or linear body with longitudinal segments; feet equally slender and elongated, and the stem of the antennae composed of several small joints. They are found among marine plants, walk like the caterpillar termed the Geometra, sometimes rapidly revolving in a circle, or turning up their body, during which time the antennse are vibrating. While swimming, the extremities of their body are curved. Leptomera, Lat. Profo, Leach. Fourteen feet, including the two annexed to the head, all complete and in a continuous series. Here, as in our Leptomera proper Gammarus pedatus, Mull., Zool. Dan., CI, 1, 2 all the feet, the two anterior excepted, have a vesicular body at their base. There, as in the Proto, Leach Cancer pedatus, Montag., Trans. Vol. III. N 98 CRUSTACEA. Lin. Soc, II, 6; Encyclop. Method., Atl. d'Hist. Nat. CCCXXXVI, 38 those appendages are only proper to the second, and four fol- lowing feet(l). Naupredia, Lat. But ten feet, all in one continuous series; the base of the second and two following pairs provided with a vesicular body(2). Caprella, Lam. Ten feet also, but in an interrupted series, commencing with the second segment, exclusive of the head; both this segment and the following have two vesicular bodies, and are totally deprived of feet(3). The other Ovalia, Lat. Lsemodipoda have an oval body with transversal segments. The stem of the antennae appears to be in- articulated, and the feet are short but slightly elongated; those of the second and third segments are imperfect and terminated by a long cylindrical joint without a hook; their base is provided with an elongated vesicular body. They form the subgenus Cyamus, Lat. Larunda, Leach. I have seen three species, all of which live on the Cetacea; the most common, Oniscus ceti, L.; Pall., Spicil. Zool. Fascic. IX, iv, 14; Squille de la Baleine, De Geer, Ins., VII, vi, 6; Pyc- nogonum ceti, Fab.; Savig., Mem. sur les anim. sans verteb., Fascic, I, v, 1, is also found on the Mackerel: it is called by fishermen Pou de Baleine. A second very analogous species was brought to France by the late Delalande from the Cape of Good Hope. The third, which is much smaller, establishes itself on the Cetacea of the Indian Ocean. (1) We should also refer to the Leptomerae the Squilla ventricosa, Mull., Zool. Dan., LVI, 1 3; Herbst, XXXVI, ii: the Cancer linearis, L., is perhaps a con- gener. He describes it as having 1 six feet, but does not include the head. (2) A subgenus founded on a species from the coast of France, which appears to me undescribed. (3) The Squilla lobata, Mull., Zool. Dan., LVI, 4, 6; his Gammarus quadrilo- batus, lb., CXIV, 12; the Oniscus scolopendroides, Pall, Spic. Zool. Fascic, IX, iv, 15, are Caprellx, but their specific differences are not well characterized. We had referred the Cancer linearis, L., to the first, which, (see note one) now ap- pears doubtful. His Cancer filiformis is probably a Caprella; the Cancer phasma, Montag., Trans. Lin. Soc, VII, vi, 2, is a congener. His figure is copied Encyc. Method , Atl. d'Hist. Nat., CCCXXXVI, 37. For details concerning this order and genus, seethe Nouv. Diet. d'Hist. Nat., Ed. II, and the work of Desmarest on the Crustacea ISOPODA. 99 ORDER V. ISOPODA(l). The Isopoda approach the Lsemodipoda by the palpi of the mandibles being absent, but are removed from them in several other respects. The two anterior feet are not at- tached to the head, and belong, as well as the following ones, to a particular segment. They are always fourteen in num- ber, unguiculated, and without any vesicular appendage at their base. The under part of the tail is furnished with very apparent appendages resembling leaflets or vesicular bursse, the two first or external of which, either partially or wholly, usually cover the others. The body is generally flattened, (1) The Polygonata, Fab., with the exception of the genus Monoculus. Messrs Audouin and Edwards Ann. des Sc. Nat., Aout 1827, p. 379, 381 have published some interesting observations on the circulation of the Isopoda, and on that of the Ligiae in particular. The heart resembles a long' vessel extended above the dorsal surface of the intestine. From its anterior extremity arise three arteries, similar to those of the Decapoda. Lateral branches are also to be observed running from the heart towards the feet. On a level with the two first segments of the abdomen (the tail), that organ receives, from the right and left, small canals (branchio-cardiac vessels) which seem to proceed from the branchiae. From their experiments on the Ligiae, it would appear that the venous system is less complete than in the Decapoda macroura, and that the blood driven from the heart into va- rious parts of the body, passes into lacunae formed between the organs in the infe- rior part of the body which communicate freely with the afferent vessels of the branchiae. The blood having traversed the respiratory apparatus, returns to the heart through the branchio-cardiac vessels. This disposition would form the tran- sition from the circulating system of the Decapoda to that of certain Branchio- poda. According to Cuvier, the two anomalous cords which form the mediate portion of the nervous system of the Onisci and, probably, of the other Isopoda and even of the Amphipoda are not in complete juxtaposition, and may be dis- tinguished throughout their whole course. There are nine ganglions without counting the brain, but the two first and two last are so closely approximated that we may reduce the number to seven. The second and six subsequent ones fur- nish nerves to the seven pairs of feet; the four anterior, although, by the order of the parts, analogous to the four last foot-jaws of the Decapoda, are true feet. The segments which immediately follow, or those which form the tail, receive their nerves from the last ganglion; these segments may be considered as simple divi- sions of one segment represented by this ganglion; thus we find that the number of these posterior segments varies. 100 CRUSTACEA. or is wider than it is thick. The mouth consists of the same pieces as in the preceding Crustacea; but here, those which correspond to the two superior foot-jaws of the Decapoda, ex- hibit an appearance of a lower lip terminated by two palpi, still more than in the latter. The two mediate antennae are almost obliterated in the last Crustacea of this order, which are all terrestrial and also differ from the others in their re- spiratory apparatus. The male organs of generation are usually announced by linear or filiform appendages, and sometimes by hooks, situated at the internal origin of the first sub-caudal laminae. The females carry their ova under the thorax, either between scales, or in a pouch or membranous sac, which they open in order to allow a passage to their young, which are produced with the form of parts peculiar to theiii species, merely changing their skin as they increase in size. Most of them are aquatic. Those which are terrestrial, like all other Crustacea which live out of water, still require a certain degree of atmospheric humidity to enable them to breathe, and to preserve their branchise in a proper state for the exercise of that function. This order according to the system of Linnaeus embraces the genus Oniscus, Lin., Which we will divide into six sections. The first Epicarides, Latr. is composed of parasitical Iso- poda, with neither eyes nor antennae, the body of which, in the male, is very flat, small and oblong; much larger in the female, and having an oval form narrowed and slightly curved posteriorly, hollow be- neath, with a thoracic border divided on each side into five mem- branous lobes. The feet are placed on this border and cannot be used either for locomotion or natation. The under surface of the tail is provided with five pairs of small, ciliated, imbricated leaflets, corresponding to as many segments and arranged in two longitudi- nal series; there is no appendage, however, to the posterior ex- tremity. The only parts distinctly visible in the mouth are two membranous leaflets laid upon another of the same nature, forming a large quadrilateral figure. The inferior concavity, forming a sort of shallow basket, is filled with the ova. Near their outlet is al- ways found the individual presumed to be the male. Its extreme ISOPODA. 101 smallness seems to forbid all possibility of copulation; according to Desmarest it is provided with two eyes; its body is straight and al- most linear. These Crustacea form but a single subgenus, that of Bopyrus, Lat., The most common species is the Bopyrus crangorum, Lat., Gener. Crust, et Insect., I, 114; Monoculus crangorum, Fab.; Fouger. de Bondar, Mem. de l'Acad. Roy. des Sc, 1772, pi. l'j Desmar., Consid. XLIX, 8 13. It lives on the Palaemon ser- ratus, and the Pal. squilla, placed directly on the branchiae and under the shell; it occasions a tumour on one of its sides, re- sembling a wen. The fishermen of the British channel con- sider them as very young Soles or Plaice. A second species, the B. des palemons, has been described by Risso, under the female of which he observed eight or nine hundred living young ones(l). The second section CYMOTHOADA,Lat. comprises Isopoda with four very apparent setaceous antennae, almost universally terminated by a pluri-articulated stem; having eyes, a mouth composed as usual(2); vesicular branchiae arranged longitudinally and in pairs; the tail formed of from four to six segments, with a fin on each side near the end; and the anterior feet usually terminated by a small stout nail or claw. They are all parasitical. The eyes are sometimes placed on tubercles on the top of the head; the tail consists of but four segments. Serolis, Leach. But a single species is known, the Cymothoa paradoxa, Fab. The antennae are placed on two lines, and terminated by a pluri- articulated stem. Under the three first segments of the tail, between the usual appendages, there are three others, trans- versal and terminated posteriorly in a point(3). Sometimes the eyes are lateral and not placed on tubercles; the tail is composed of five or six segments. Here the organ of sight is not formed of smooth, granular, ap- proximated eyes; the antennae are placed on two lines, and consist of seven joints at least; the six anterior feet are usually terminated by a small, stout nail. (1) See the work of Desmarest, who has completely described this subgenus. (2) See our general observations on the Malacostraca with sessile eyes. (3) For other details consult Desmar., Consid., p. 2y2 294. 102 CRUSTACEA. In some, where the tail always consists of six segments, the length of the inferior antennae never surpassed the half of that of the body. We will begin with those whose mandibles, as usual, are but slightly, or in no degree salient. Cymothoa, Fab. The antennae nearly equal in length; eyes scarcely apparent; last segment of the tail forming a transverse square; the two pieces ter- minating the lateral fins, linear, equal and styliform(l). Icthyophilus, Lat. Nerocila, Livoneca, Leach. The antennae, equal in length, and but slightly visible eyes; the last segment of the body almost triangular; the two pieces termi- nating the lateral fins in the form of leaflets or laminae, the exterior of which is largest in the Nerocilae, and of the size of the other in Livoneca(2). In the four following subgenera the superior antennas are mani- festly shorter than the inferior. In several, as in Cymothoa, all the feet are terminated by a small, stout, and strongly curved nail; the last eight are not spinous; the eyes are always separated and convex. They form three genera in the system of Leach, but may be united in a single subgenus, under the common denomination of one of them, or the Canolira, Leach. Anilocra, Olencira, Ejusd. The laminae of the fins in the Olencirae(S) are narrow and armed with spines. In the Anilocrae(4) the external leaflet of the same parts is longer than the internal; the reverse is the case with the Canolirae(5). The eyes, besides, are but slightly granulous while in the preceding that disposition is evident. In the three following subgenera, the second, third and fourth feet alone are terminated by a strongly curved nail, and the last eight are spinous. The eyes are usually but slightly convex; they are large and converge anteriorly. (1) Cymothoa sestrum, Fab.; Desmar., Consid., XLVI, 6, 7; C. imbricata, Fab. For the other species, see Desmar., loc. cit. (2) See Desmar., op. cit., p. 307, genera Nerocila and Livoneca, and various spe- cies of Cymothoae of Hisso, p. 310, 311. (3) Desmar., Consid., p. 306. (4) Desmar., Consid., Anilocre du Cap, XLV1II, 1- (5) Desmar., Consid., p. 305. ISOPODA. 103 jEga, Leach. The two first joints of the superior antennae very broad and com- pressed, while in the two subsequent subgenera they are almost cy- lindrical^). Rocinela, Leach. The Rocinelae differ from the iEgae, as just stated, in the form of the two first joints of their superior antennae, but otherwise approach them, as in their large eyes which approximate anteriorly(2). The Conilira, Leach, Resembles Rocinela in the antennae; but the eyes are smaller and distant, and the edges of the segments nearly straight and not falciform nor prominent(3). The last subgenus, among those of this section in which the an- tennae are placed on two lines, where the tail is composed of six segments, and the inferior antennae are always short, is distin- guished from all the preceding by strong and salient mandibles. It is the Synodus, Lat., A subgenus established on a single species(4). In those that follow, the tail is usually composed of but five seg- ments. The length of the inferior antennae is more than the half of that of the body. Cirolana, Leach. The tail composed of six segments(5). In the Nelocira, Leach, It consists of but five. The cornea of the eyes is smooth(6). Eurydice, Leach. Similar to Nelocira in the number of caudal segments, but re- moved from it by the granulous eyes(7). (1) Desmar., Consid., p. 304, JEga entaillee, XLVII, 4, 5. (2) Desmar., Consid., p. 304. (3) Desmar., Consid., p. 304. (4) SeeEncyc. Method., article Synodus. (.5) Desmar., Consid., p. 303. (6) Desmar., Consid., p. 302; Ndocire de Swainson, XL VIII, 2. (7) Desmar., Consid., p. 302. 104 CRUSTACEA. This subgenus leads us to those in which these organs are formed of granules or approximated simple eyes, and that also have the four antennse, composed of four joints at most, inserted on one hori- zontal line, and all the feet fitted for walking. The tail consists of six segments, the last of which is large and suborbicular. Such is the Limnoria, Leach. The only living species known is the Limnoria terebrans, Leach, Edinb. Encyclop., VII, p. 433; Desmar., Consid., p. 312. Although scarcely above two lines in length, its habits and fecundity render it highly noxious. It perforates the tim- bers of ships in various directions and with alarming rapidity. When taken in the hand it rolls itself into a ball. It is found in various parts of the British seas. The figure and description of a small fossil crustaceous ani- mal has been sent to Count Dejean by Professor Germar, which seems to us to belong to this subgenus(l). The third section Sph^eromides, Lat. exhibits four very dis- tinct, short, setaceous or conical antennse, and a single genus An- thura excepted, always terminated by a stem divided into several small joints; the inferior, always the longest, are inserted beneath the under part of the first joint of the superior which is broad and thick. The arrangement of the mouth is as usual. The branchiae are vesicular or soft, exposed, and arranged longitudinally in pairs. But two complete and movable segments are observed in the tail, the first, however, frequently presents impressed and transverse lines indicating vestiges of others; on each side of its posterior ex- tremity is a fin terminated by two leaflets, of which the inferior alone is movable; the superior(2) is formed by an internal prolongation of the common stem. The branchial appendages are curved in- wards; the inner side of the first are accompanied, in the male, by a small linear and elongated projection. The anterior part of the head situated beneath the antennse is triangular, or has the figure of a heart reversed. Some have an oval or oblong body, usually assuming, when con- tracted, the form of a ball; the antennse terminated by a pluri-articu- lated stem, and the inferior, at least, visibly longer than the head. (1) The Oniscus prsegustator, figured in Parkinson, is allied to this species, or at least appears to belong to the same section. (2) It folds over the posterior edge of the last segment, and in several, such as the Zuzarae, and Naess, Leach, like an arch. ISOPODA. 105 The lateral and posterior fins are composed of a peduncle and two laminae, forming with the last segment a common fin shaped like a fan. In these, the impressed and transverse lines of the anterior seg- ment of the tail, which is always shorter than the next or last one, do not extend to the lateral margin. The first joint of the superior antennae has the form of a triangular palette. The head, viewed from above, forms a transverse square. The leaflets of the fins are much flattened, and the intermediate piece or the last segment is widened and rounded laterally. Zuzara, Leach. Leaflets of the fins very large; the superior, which is the shortest, separates from the other to form a border to the last segment(l). Sphjeroma, Lat. Leaflets of a moderate size, equal, and laid one over the other(2). In those, the impressed lines or transverse sutures of the anterior segment of the tail extend to its lateral edges and cut it. The first joint of the superior antennae forms an elongated square, or linear palette. The leaflets of the fins are usually narrower and thicker than in the preceding ; the external sometimes (Cymodocea) incloses the other, which is prismatic ; the point at which they unite resembles a knot or joint. Sometimes the sixth segment of the body is visibly longer through- out all its width than the preceding ones and that which follows. Only one of the two leaflets projects. Njesa, Campecopea, Leach(3). Sometimes the sixth segment of the body is as long as the preced- ing ones and as that which follows. Cilicea, Leach. Only one of the fin-leaflets salient, the other being placed against the posterior edge of the last segment(4). (1) Desmar., Consid., p. 298. (2) Desmar., Consid., p. 299302. Spherome derive, XLVII, 3;0niscus ser- ratus, Fab. (3) Desmar., Consid., Nes4e bidentt, XLVII, 2;Campecopee velue, Id., It., 1. (4) Desmar., Consid., Cilicee de Latreille, XLVIII, 3. Vol. III. O 106 CRUSTACEA. Cymodocea, Leach. Both leaflets salient and directed backwards ; the sixth segment is not prolonged posteriorly, and the extremity of the last one pre- sents a small lamina in an emargination(l). Dynamene, Leach. Similar to the Cymodoceae in the projection and direction of the leaflets of the fins, but the sixth segment is prolonged posteriorly, and the last one exhibits a mere fissure without the lamina(2). The others,- such as the Anthura, Leach, Have a vermiform body, and the antennae, composed of four joints, scarcely as long as the head. The leaflets of the posterior fins by their disposition and approximation form a sort of capsule. The anterior feet are terminated by a monodactyle forceps(3). In the fourth section Idoteides, Leach there are also four an- tennas, but they are placed on one horizontal and transverse line; the laterals terminate in a tapering, pointed, pluriarticulated stem ; the intermediaries are short, filiform or slightly inflated at the end, and consist of four joints, neither of which is divided. The compo- sition of the mouth is the same as in the preceding sections. The branchiae, white in most of them, are in the form of bladders, sus- ceptible of inflation, serving for natation and covered by two lami- nae or valvulae of the last segment that adhere laterally to its edges j they are longitudinal, biarticulated, and open in the middle on a straight line like folding doors. The tail consists of three seg- ments, the last of which is much the largest, and has neither termi- nal appendages nor lateral fins. They are all marine. Idotea, Fab. All the feet alike, and strongly unguiculated ; the body oval or simply oblong, and the lateral antennae shorter than half the length of the body(4). (1) Desmar., Consid., XLVIII, 4. (2) Desmar., Consid., p. 297. (3) Desmar., Consid., Anthure grtle, XLVI, 13; Oniscus gracilis, Montag., Trans. Lin. Soc. IX, v, 6; Gammarus keteroclitus, Vivian., Phosph. Mar., II, 11, 12. (4) Oniscus entomon, L. ; Squilla entomon, Deg. , Insect., VII, xxxii, 1, 2; Idotea tricuspidata, Latr.; Desm., Consid., XLVI, ii. For the other species, see Idotea, Nouv. Diet. d'Hist. Nat., Ed. II, and Desmar. op. cit. ISOPODA. 107 Stenosoma, Leach. The Stenosomae only differ from the Idotese in the linear form of their body, and the length of their antennae which is more than half that of the body(l). Arcturus, Lat. The Arcturi are very remarkable for the form of the second and third feet, which incline forwards and terminate by a long, bearded and unarmed or feebly unguiculated joint; the two anterior are laid on the mouth and are unguiculated; the last six are strong, ambu- latory, thrown behind, and bidentated at the extremity. In the length of the antennae and form of the body they approach the Ste- nosomae. I have never seen but a single species, the JLrct. tuberculatus, which was brought to Europe, from the Arctic seas, in one of the last expeditions to those regions. The fifth section Asellota, Lat. comprises Isopoda with four very apparent setaceous antennae, arranged on two lines, and termi- nated by a pluriarticulated stem; two mandibles; four jaws covered, as usual, by a kind of lip formed by the first foot-jaws; vesicular branchiae, in pairs, covered by two longitudinal and biarticulated, but free leaflets; a tail composed of a single segment, without late- ral fins, but with two bifid stylets, or two very short tubercular ap- pendages on the middle of its posterior edge. Other lamelliform appendages, situated at its inferior base, which are now numerous in the males, distinguish the sexes. Asellus, Geoff. Two bifid stylets at the posterior extremity of the body ; eyes separated; the superior antennae at least as long as the peduncle of the inferior ; the hooks at the end of the feet entire. The only species of this subgenus that is known the Aselle d'eau douce, Geoff., Ins. II, xxii, 2; Squille aselle, Deg., Insect., VII, xxi, 1; Desmar., Consid., XLIX, 1,2; Jdotea aquatica, Fab., is very abundant in fresh and stagnant waters as well as in the marshes, in the vicinity of Paris. Its gait, unless alarm- ed, is very slow. In the spring it issues from the road in which (1) Stenosoma Uneare, Leach; Desmar. op. cit. lb. xlvi, 12; Stenosoma hecticum, lb. ; Idotea viridissima, Risso, Crust, III, 8. For the other species, see Desmar. op. cit. 108 CRUSTACEA. it has passed the winter. The male, much larger than the fe- male, carries the latter for eight days, clasping her with the fourth pair of feet. When he abandons her she is loaded with a great number of ova inclosed in a membranous sac, situated under the thorax, which affords an issue to the young through a longitudinal fissure. Oniscoda, Lat. The Oniscodse or Janirje(l) of Leach differ from the Aselli in the approximation of their eyes, in the superior antennae which are shorter than the peduncle of the inferior, and in the hooks of the tarsi which are bifid. The only species known, the Janira maculosa, Leach; Des- mar., Consid., p. 315, was found on the coast of England among the Fuci and Ulvse. Jjera, Leach, But two tubercles at the extremity of the tail in place of the stylets. But a single species has been described, the gsera albifrons, Leach; Desm., Consid., p. 316, which is very common on the English coast among the Fuci and Ulvae. Finally, the Isopoda of the sixth and last section Oniscides, Lat. have four antennae also, but the two intermediate ones are very small, but slightly apparent, and are composed at most of but two joints; the lateral are setaceous. The tail consists of six segments, with two or four styliform appendages on the posterior margin of the last one, and is without lateral fins. Some of them are aquatic and others terrestrial. In the latter, the first leaflets of the under part of the tail exhibit a series of small holes, through which air penetrates to the organs of respiration therein contained. In some, the sixth joint of their antennae, or the stem, is so com- posed, that by counting the little joints of this part the total num- ber amounts at least to nine. These Isopoda are marine and form two subgenera. The Tylos, Lat., Appears \o possess the faculty of rolling itself into a ball. The (1) A name employed by Risso for a genus of the same class; I have conse- quently been obliged to repUce it with another. ISOPODA. 109 last segment of the body is semicircular, and exactly fills up the emargination formed by the preceding one; the posterior appendages are very small and entirely inferior. The antennae consist of nine joints, the last four composing the stem. On each side is a de- pressed tubercle representing one of the intermediate antennae; the intervening space is raised. The branchiae are vesicular, imbricated, and covered by laminae(l). Ligia, Fab. The stem of the lateral antennae composed of a great number of small joints ; two very salient stylets divided at the end into two branches, at the posterior extremity of the body. Ligia oceanica ; Oniscus oceanicus, L., Desmar., Consid., XLIX, 3, 4, about an inch long, grey, with two large yellowish spots on the back. The lateral antennae are less than half the length of the body, and their stem consists of thirteen joints. The stylets are as long as the tail. This animal is very com- mon on the coast of France, where it is seen climbing up the rocks, 8cc. If an attempt be made to capture it, it quickly folds up its feet and lets itself fall. In the Ligia italica, Fab., the lateral antennae are nearly as long as the body; the sixth joint, or the stem, is divided into seventeen small ones. The stylets are much longer than the tail. . Ligia muscorum; Oniscus hypnorum, Fab., Cuv., Journ. d'Hist. Nat. II, xxvi, 3, 4, 5; Oniscus agilis, Panz., Faun., Ins. Germ., Fascic. IX, xxiv. The lateral antennae shorter than the half of the body, and their stem composed of but ten small joints. The peduncle of the posterior stylets is furnished on the inner side with a tooth and seta. In others, all terrestrial, the lateral antennae consist at most of eight joints which gradually diminish in size towards the extremity, so that no one of them appears to be divided or compound. Here, the posterior appendages, or stylets, project beyond the last segment. The body does not contract into a ball, or does it im- perfectly. Philoscia, Lat. The lateral antennae divided into eight parts and exposed at base; (1) Tylos armadillo, Lat., fig. in the pi. d'Hist. Nat. of the great work on Egypt from the Mediterranean. 110 CRUSTACEA. the four posterior appendages nearly equal. They are only found in wet places(l). Oniscus, Lin. The true Onisci have also eight joints in their lateral antennas, but their base is covered, and the two external appendages of the extremity of the tail are much larger than the others. These ani- mals, and those of the two following subgenera are vulgarly called Clous-a-porte, and by syncope Cloporte, Porcelets de Saint -Jlntoine(2). They inhabit retired and obscure places, cellars, fissures in walls, old buildings, under stones, Sec, 8cc. They feed on decaying vege- table and animal matters, and seldom issue from their retreat, ex- cept in rainy weather. They move but slowly, unless they are alarmed. The ova are inclosed in a pectoral pouch. The young, at birth, have one thoracic segment less than the adult, and conse- quently have but twelve feet. They are no longer employed in medicine(S). Porcellio, Lat. The Porcelliones differ from the Onisci in the number of joints that compose the lateral antennae, which is only seven. In their other characters they are alike(4). There, as in Armadillo, Lat. The posterior appendages of the body do not project; the last segment is triangular; a little lamina resembling a reversed trian- gle, or widest and truncated at the end, formed by the last part of the lateral appendages, fills, on each side, the space between that segment and the preceding one. The lateral antennas have but (1) Oniscus sylvestris, Fab.; Oniscus muscorum, Cuv., Journ. d'Hist. Nat. II, xxvi, 6, 8; Coqueb., 111. Icon. Insect, Dec. I, vi, 12. (2) These "Pigs of St Anthony" are our Wood-Lice Boiled in milk they still constitute a favourite remedy with numerous patients, and some few equally in- telligent practitioners, who attribute to them diuretic, absorbent, and aperient qualities. That they may act as an emetic, I can readily admit. Am. Ed. (3) Oniscus murarius, Fab.; Cuv., Journ. d'Hist. Nat., II, xxvi, 11, 13; Le Clo- porte ordinaire, Geoff., Insect. II, xxii, 1; Cloporte aselle, Beg., Insect. VII, xxxv, 3; Desmar. Consid., XLIX, 5. (4) Oniscus asellus, Cuv., lb.; Panz., Faun. Ins. Germ., IX, xxi; Cloporte ordi- naire, var. C, Geoff; Porcellio kevis, Latr.; Cloporte ordinaire, var. B, Geoff. ISOPODA. Ill seven joints. The superior subcaudal scales exhibit a range of small holes(l). (1) Oniscus armadillo, L.; Cuv., lb., 14, 15; Oniscus cinereus, Panz.,Ib., Fascic. LXII, xxii; Oniscus variegatus, Vill., Entom., IV, xi, 16; Armadilh pustuli, Des- mar., Cortsid., XLXIX, 6; Armadilh des boutiques, Dumer., Diet, des Sc. Nat, III, p. 117, a species from Italy formerly employed by the apothecaries. 112 CRUSTACEA. SECOND GENERAL DIVISION. ENTOMOSTRACA. Under this denomination, which is taken from the Greek and signifies Insects with shells, Othon Frederick Muller comprises the genus Monoculus of Linnaeus, to which we must add some of his Lernasse. His investigation of these animals, the study of which is so much the more difficult as they are mostly microscopic, and the observations of Schseffer and of M. Jurine, Sen., have excited the admiration and secured the gratitude of every naturalist. Other but partial labours such as those of Randohr, Straus, Herman, Jun., Ju- rine, Jun., A. Brongniart, Victor Audouin, and Milne Ed- wards, have extended our knowledge of these animals and particularly of their anatomy ; but in this respect, Straus, as well as M. Jurine, Sen., although preceded by Randohr in the observation of several important details of organization, of whose memoir on the Monoculi, 1805, they seem to have been ignorant, has surpassed them all. Fabricius merely adopted the genus Limulus of Muller, which he placed in his class of the Kleistagnatha, or our family Brachyura of the order De- capoda. All the other Entomostraca are united as by Lin- nseus in one single genus, Monoculus, which he places in his class of the Polygonata or our Isopoda. These animals are all aquatic and mostly inhabit fresh wa- ter. Their feet, the number of which varies, and that some- times extends to beyond a hundred, are usually fitted for natation only, being sometimes ramified or divided, and some- times furnished with pinnulse or formed of lamella?. Their brain is formed of one or two globules. The heart has always the figure of a long vessel. The branchiae, composed of hairs or setae, singly or united, in the form of barbs, combs or tufts, ENTOMOSTRACA. 113 constitute a part of those feet or of a certain number of them, and sometimes of the upper mandibles(l). Hence the origin of our term Branchiopoda, affixed to these animals, of which at first we formed but a single order. Nearly all of them are provided with a shell composed of one or two pieces, very thin, and most generally almost membranous and nearly diaphanous, or at least with a large anterior thoracic segment, frequently confounded with the head, which appears to re- place the shell. The teguments are usually rather horny than calcareous, thereby approximating these animals to the Insecta and Arachnides. In those which are provided with ordinary jaws, the inferior or exterior are always exposed, all the foot-jaws performing the office of feet properly so called, and none of them being laid upon the mouth. The second jaws, those of the Phyllopa at most excepted, resemble these latter organs ; Jurine sometimes distinguishes them by the name of hands. These characters distinguish the gnawing Entomostraca from the Malacostraca ; the others, those which constitute our order of the Pcecilopoda, cannot be confounded with the Malacostraca, inasmuch as they are deprived of organs of mas- tication, or because the parts which seem to act as jaws are not united anteriorly nor preceded by a labrum as in the an- tecedent Crustacea and the gnawing Insecta, but are simply formed by the branches of the locomotive organs, which, for that purpose, are furnished with small spines. The Pcecilo- poda in this class of animals represent those which in that of Insects are knowii by the name of Suctoria or the Suckers. Nearly all of them are parasitical, and they seem to lead to the Lernsese by insensible gradations ; but the presence of eyes, the faculty of changing their skin, or even of undergo- ing a sort of metamorphosis(2), and that of locomotion by (1) See Cypris. (2) The young of Daphnia, and of some neighbouring- subgenera, and probably also those of Cypris and Cytherea, with the exception of size, scarcely differ, if at all, from their parents on quitting the egg; but those of Cyclops, the Phyllopa, and the Arguli, experience considerable changes while young, either as respects Vol. III. P 114 CRUSTACEA. means of their feet, appear to us to establish a positive line of demarcation between the former and the latter. We have consulted several erudite naturalists with respect to these transformations, but none of them have observed a change of skin to occur. The antennae of the Entomostraca, whose form and number greatly vary, serve for natation in several. The eyes are rarely placed on a pedicle, and when this is the case, that pedicle is a mere lateral prolongation of the head, and is never articulated at base ; they are frequently closely ap- proximated and even form but one. The organs of genera- tion are situated at the origin of the tail ; it has been thought, but erroneously, that their seat was in the antennse of the male. This tail(l) is never terminated by a fan-like fin, nor does it present those false feet observed in the Malacostraca. The ova are collected under the back, or are external, and covered by a common envelope, and resemble one or two small clusters at the base of the tail ; it appears that they can be kept in a desiccated state for a long period without losing their properties. It is only after a third change of skin that these animals become adult and capable of continuing their species. It has been proved, with respect to some of them, that a single copu- lation fecundifies several successive generations. ORDER I. BRANCHIOPODA. A mouth composed of a labrum, two mandibles, a ligula, and one or two pairs of jaws, and branchiae, the first of the form of the body or the number of feet. These organs in some, the Arguli for instance, experience changes which modify their uses. (1) If we except the Phyllopa, the last feet are thoracic, or foot-jaws (Cypris). BRANCHIOPODA. 115 which, when there are several, are always anterior, charac- terize this order or the sixth of the class. These Crustacea are always wandering and are generally protected by a shell resembling that of a bivalve, and fur- nished with four or two antennae. Their feet, with a few exceptions, are wholly natatory. Their number varies, be- ing but six in some, while in others it amounts to twenty, for- ty-two, or more than a hundred. Many of them have but one eye. Most of these animals, as we have already stated, being nearly microscopical, it is evident that the application of one of the characters we have employed that of the presence or absence of the palpi of the mandibles with respect to them, presents almost insuperable difficulties(l). The form and number of the feet, that of the eyes, the shell, the antennas, furnish us with more visible marks, and such as are within the observation of every one. This order in the systems of De Geer, Fabricius and Lin- naeus, a single species excepted M. polyphemus, contained but the single genus Monoculus, Lin. (2) Which we will divide into two principal sections. The first, that of the Lophyropa is distinguished by the number of feet, which never extends beyond ten; their joints are also more or less cylindrical or conical, and never entirely lamelliform or foli- aceous; the branchiae are but few in number, and most of them have but one eye. Several, besides, have mandibles provided with a palpus(3); there are, almost always, four antennae which serve for locomotion. In the second section that of the Phyllopa the number of feet is increased to at least twenty, and in some amounts to many more; their joints, or at least the last ones, are flattened and resemble cili- (1) We will begin, however, with those Uranchiopoda whose mandibles are furnished with palpi; they constitute the two first divisions of the Lophyropa. (2) And that of Binocle in the system of Geoffroi. (3) M. Straus appears to attribute this character exclusively to Cypris and Cy- therea, which compose his order of the Ostrapoda; but from the observations of Jurine, Sen., and Handohr, it seems that it also belongs to Cyclops. 116 CRUSTACEA. ated leaflets. The palpi of the mandibles are always wanting. They all have two eyes, situated in some at the extremity of two movable pedicles; their antennae, but two in number in several, are generally small and not fitted for natation. We will divide the Lophyropa into three principal and very natu- ral groups, the two first of which approach the Crustacea of our three first orders in their mandibles, each of which is furnished with a palpus, and in some other characters. 1. Those Carcixoida, Lat. whose more or less ovoid shell is not doubled like that of a bivalve, and leaves the inferior portion of the body exposed. They never have antennae resembling ramified arms. They have ten feet, more or less cylindrical or setaceous. The ova, in those females whose gestation has been observed, are contained in two external sacs situated at the base of their tail. Some of them have eyes. 2. Those Ostracoda, Lat.; Ostrapoda, Straus whose shell is formed of two pieces or valves resembling those of a muscle, united by a hinge, and closing while the body is quiescent. They have but six feet(l), neither of which terminates in a digitated fin, nor is ac- companied by a branchial lamina. Their antennae are simple, fili- form or setaceous. They never have more than one eye. Their mandibles and superior jaws are furnished with a branchial leaf. The ova are placed under the back. 3. The last Cladocera, Lat.; Daphnides, Straus have but one eye, and the shell doubled but without a hinge (Jurine), termi- nating posteriorly in a point, and leaving the head, which is cover- ed by a kind of shield like a rostrum, exposed. They have two, usually very large, antennae, resembling arms, divided into two or three branches directly above the peduncle, which are furnished with threads, always projecting and serving as oars. Their ten feet(2) are terminated by a digitated or pectinated fin accompanied, the two first excepted, by a branchial lamina(3). Their ova are also placed under the back; their body always ter- minates posteriorly in the manner of a tail, with two or three threads at the end. The anterior extremity of the body is sometimes pro- (1,) According to Straus, the first pair of feet; but although these parts by serv- ing as oars perform their functions, I nevertheless consider them as analogous to the lateral antennae of the superior Crustacea and to the two superior ones of a Cyclops, which here also concur with the feet in producing locomotion. (2) Midler gives eight to the Cytherea;; reasoning from analogy, we may pre- sume that he was mistaken. (3) This character applies especially to Daphnia, the most numerous subgenus of this division, and by analogy, to Polyphemus and Lynceus. BRANCHIOPODA. 117 longed into a kind of rostrum, and at others forms a kind of head, almost entirely occupied by a large eye. The first division of the Lophyropa Branchiopoda that of the Carcinoida may be divided into two according to the number of the eyes. Some of them have two. Here the shell completely invests the thorax; the eyes are large and very distinct, and the intermediate antennae are terminated by two threads. Zoea, Bosc. Very large globular eyes completely exposed, and horn-like pro- jections on the thorax. Zoea pelagica, Bosc, Hist. Nat. Crust. II, xv, 3, 4. The body semi-diaphanous; four antennae inserted under the eyes, the external ones bent into an elbow and bifid; a kind of long rostrum on the forepart of the thorax and between the eyes, and a long pointed prominence on the posterior part of the back. The feet are very short and hardly visible, the two last excepted, which are elongated or terminate in a fin. The tail is as long as the thorax, curved, and formed of five joints, the last being large, crescent-shaped and spinous. It was discovered by Bosc in the Atlantic Ocean. The Monoculus taurus, Slabber, Microsc. V, and the Cancer germanus, L., appear to be allied to it(l). Nebalia, Leach. Triangular, flattened eyes, partly covered by a triangular and arched scale. The feet are forked, and the terminal appendages of the tail seta- ceous^). (1) See the Hist. Nat. des Crust, et des Insect., of Latreille, and the work of Desmaresl on the Crustacea. This genus has not yet been completely described, and we have not been able to procure a single specimen of it. (2) Nebalia Herbstii,Lea.ch, Zool. Miscell., XLV; Desmar., Consid., XL, 5; Rand., Monoc. I, 8? The Nebalie ventrue, Risso, Journ. de Phys., Octob. 1822, probably forms a pe- culiar subgenus in the section of the Schizopoda. In the Cyclops exiliens, Viviani, the thorax is divided into several segments, a circumstance which excludes it from the Nebaliae. It also forms a new subgenus intermediate between the preceding and following one. N.B. A new species of this genus, the N. Geoff. Saint-Hil., lb., XV, 1, has been very minutely described by Milne Edwards. The head is terminated anteriorly by 118 CRUSTACEA. There, the thorax or the shell, viewed from above, is divided into five segments, of which the first is much the largest and has the an- tennae, eyes, and foot-jaws attached to it; the second and the third have each one pair of feet, the fourth has the two following pairs, and the fifth, the last. The eyes are small and not prominent; all the antennae are terminated by a single thread. CoNDYLURA, Lat. The inferior antennsa longest; the anterior sides of the first seg- ment prolonged into a point forming two scales approximated into a kind of rostrum; feet terminating in a silky point; some of the intermediaries, as in the Schizopoda, with an external appendage near their base; the tail narrow and formed of seven annuli, the last of which, conical and elongated, projects between the two lateral appendages that are slender, styliform, and composed of two joints, the lastsilky(l). We should remark, that the genus Nicothoe of MM. Audouin and Milne Edwards, by admitting it to have mandibles and jaws, would belong to this section; but as the animal on which it is founded is parasitical, and, as I think I perceived in it a vestige of a sucker, I have placed it among the Poecilopoda. I would observe, however, that the feet, the anterior excepted, closely resemble those of Cyclops, and that the females also carry their ova in two sacs situated at the base of the tail as in the latter genus(2). a rostrum articulated at base, or movable and pointed; the eyes are pedunculated; the superior antennae are inserted under them, and the second joint of their .pe- duncle isfurnisbed vvitb a lamina; the mouth is surrounded with three pairs of ap- pendages which appear to us to correspond in their progressive order to the pal- pigerous mandibles and four jaws of the Crustacea Decapoda; beneath are placed five pairs of foliaceous and ciliated laminae which appear to be branchial, and fur- ther down are four pairs of bifid and natatory feet; the abdomen is composed of seven annuli, the first of which support two small rudimental filaments; the last is terminated by two elongated stylets furnished with long hairs. As it is extremely probable that there is, as usual, another pair of feet, the two inferior and branchial appendages above mentioned, may very well represent that pair. In the other appendages we should find foot-jaws and the parts of the ligula; in that case the Nebalice must be referred to the last section of the Decapoda Macroura. (1) Condylura Dorbigni, Lat. From the sea coast of Kochelle. (2) Near the Condylurae should be placed the genus Cuma, M. Edwards, Ann. des Sc. Nat. XIII, xiii, B. The superior antennae are rudimental, and consist of but one joint. The head is distinct from the thorax which is divided into four seg- ments, to the first of which are attached the four anterior feet, each of the follow- ing having a pair; all these feet are natatory, directed forwards, and have no hook at the end; the two first pairs alone are bifid. BRANCH10P0DA. 119 In the remaining Lophyropa of our first division, the thorax, as in the Condylura, is divided into several segments, the first of which is much the largest; they have bufJBne eye situated in the centre of the front between the superior antennas. Such is the Cyclops, Mull., So well studied by Jurine, Sen., and Randohr. The body is more or less oval, soft or gelatinous, and divided into two portions, one anterior, composed of the head and thorax, the other posterior, or the tail. The segment immediately preceding the sexual organs, and which, in the female, is provided with two appendages in the form of little feet fulcra, Jurine may be considered as the first of the tail, which is not always decidedly or suddenly distinguished from the thorax. It is composed of six parts or segments; under the second in the males, are two articulated appendages, sometimes sim- ple, and at others with a small branch on the inner side of various forms, and constituting, either wholly or partially, the organs of gene- ration. The vulva, in the other sex, is situated on the same segment. The last one is terminated by two points or stylets, forming a fork, and is more or less furnished with setae or penniform threads. The other or anterior portion of the body is divided into four segments, the first of which is much the largest, and composes the head and part of the thorax, which are also covered by a common scale. In it, are inserted the eye, four antennae, two mandibles mandibules internes of Jurine, furnished with a palpus, either simple or di- vided into two articulated branches, two jaws mandibules externes, or levre avec des barbillons of Jurine(l), and four feet, each di- vided into four cylindrical stems furnished with hairs or bearded threads; the anterior pair, corresponding to the second jaws, differs slightly from those that follow. Jurine compares it to a kind of The genus Pontia, Id., lb., XIV, appears to us to approach Cyclops. The head is distinct from the trunk, and terminated by a rostrum which is rather acute and appears to be formed of two pieces; it has two sessile eyes; four antennae, the superior of which are setaceous, multi-articulated and ciliated; the inferior are pediform, composed of a peduncle, serving as a base to two divisions or branches, each terminated by a pencil of hairs, one of them having two joints, the last widened at the end, and the other consisting of one. The thorax is divided into five annuli, and has six pairs of natatory and bifid feet. The abdomen is formed of two segments and terminated by two spatula-like appendages or fins. (1) According to the successive order of the parts of the mouth in the Deca- poda, the part situated immediately beneath the mandibles is the ligula; but the dentation of those here spoken of indicates maxillary organs. The ligula may have escaped the notice of M. Jurine. 120 CRUSTACEA. hands. To each of the three following segments, is attached a pair of feet formed like the two last^f the preceding ones. Two of the antennae, superior to the others^are longer, setaceous, simple, and composed of numerous small joints; by their action, they facilitate the motion of their body, and almost perform the office of feet. The inferior antennales, Jurine are filiform, usually present but four joints, are sometimes simple, and at others, forked; by the ra- pidity of their motions in the water, they occasion a kind of whirl- pool. In the males, the superior antennae, or one of them only (C. castor) are marked by a strangulation and dilatation, followed by a joint with a hinge. By means of these organs, they seize their fe- males, in their amorous preludes, either by the posterior feet, or by the extremity of the tail, and keep them, nolens volens, in the pecu- liar position in which they fix themselves. The latter carry off the males, when they are unwilling to gratify their desires on the spot. The business of coition is performed, as in the preceding Crustacea, and by prompt and repeated acts. Jurine observed it to occur three times in the space of fifteen minutes. Until the publica- tion of his remarks, it was thought that the male organs of gene- ration were placed on the superior antennae, and this error appear- ed to be the more probable, inasmuch as an analogous conformation was known to exist in the Araneides. On each side of the tail, in the female, is an oval sac, filled with eggs ovaire externe, Jurine adhering by a very slender pedicle to the second segment, close to its junction with the third, where the orifice of the oviduct is also visible. The pellicle, forming these sacs, is a mere continuation of that of the internal ovary. The number of ova they contain aug- ments with age; they are at first brown or dark, afterwards become reddish, and when the young ones are about to be hatched, are al- most transparent, but without increasing in size. If insulated or detached, at least until a certain period, the germ perishes. A single, but indispensable fecundification suffices for several success- ive generations. The same female may spawn ten times in the space of three months. Allowing it to occur but eight times in that period, and the number of young ones produced to be forty, the sum total of births will amount to near four thousand five hundred mil- lions. The length of time which the young remain in the ovaries, varies from two to ten days, according to the temperature of the season, and various other circumstances. The oviferous sacs sometimes present a greater or less number of elongated glandiform bodies which appear to consist of a collection of Infusoria. The young, at birth, have but four feet, and their body is round- ed and without a tail. It was with these that Muller formed his genus Amymone. Some time after fifteen days, from February to BRANCHIOPODA. 121 March they acquire another pair of feet, constituting the genus Nauplias, Muller. After the first change they have the form and all the parts which characterize the adult animal, but more exiguously proportioned; their antennae and feet are proportionally shorter. After thrice changing their skin they are capable of propagation. Most of these Entomostraca swim on their back, dart about with great vivacity, and move both backwards and forwards with equal facility. For want of animal substances they will attack vegetable matters, but the fluid in which they live does not pass into their stomach. The alimentary canal extends from one extremity of the body to the other. The heart in the C. castor is oval, and situated under the second and third segment of the body; a vessel is given off at each of its extremities, one running to the head, and the other to the tail. Directly under it is a second analogous, but pyriform or- gan, which also produces a vessel at each end, corresponding per- haps to the branchio-cardiac canals, mentioned in our observations on the circulation of the Crustacea Decapoda. From several expe- riments made by Jurine upon various Cyclopes, alternately asphyxi- ated and resuscitated, it would appear that in this sort of resurrec- tion the extremity of the intestinal canal gives the first signs of life, and that the irritability of the heart is less energetic; that of the an- tennas, in the males especially, of the palpi, and lastly of the feet, is inferior. No alteration is effected in the antennae by amputating a portion of them; the reintegration takes place under the skin, for the organs reappear in all their entireness at the ensuing moult. The C. staphylinns, from its shorter antennae, the superior of which consist of a considerably less number of joints than those of other Cyclopes, while the inferior, on the contrary, have more; and from the shape of its body which gradually diminishes towards its poste- rior extremity, so that it seems to have no tail or at least none that is abruptly formed, and its back, in the females, being armed with a kind of horn posteriorly arcuated, forms a particular division. The C. castor, and some others whose inferior antennae and mandibular palpi are divided above their base into two branches, may also com- pose another group. The one designated by Leach under the gene- ric name of Calanits, might in fact constitute a separate subgenus, if it were true that the animal on which it is founded had no inferior antennae; but has that gentleman satisfied himself that such is the fact, by personal observation, or does he depend upon the assertion of Muller? C. quadricomis; Monoculus quadricomis^ L. ; Mull., Entom., XVIII, 1 14; Jurine, Monoc, I, II, III. All the antennae sim- ple or undivided; the inferior with four joints, and their length Vol. III. Q 122 CRUSTACEA. hardly equal to one-third of the others; the body, properly so called, inflated and almost ovoid; tail narrow and formed of six segments. The colour varies greatly; some are reddish, others whitish or greenish. The whole length of the animal is two lines. This species is very common(l). The second general division of the Lophyropa Branchiopoda, or that in which the shell is formed of two valves united by a hinge Ostracoda, Lat. ; Ostrapoda, Straus is composed of two subge- nera, the first of which, Cythere, since the interesting and valuable observations of the latter upon the second or Cypris, appears to solicit a more profound examination than that of Midler, our only authority with respect to its characters, in order that they may be clearly defined. According to Miiller we find in the Cythere, Mull. Cytherina, Lam. Eight simple feet(2), terminating in a point, and two equally sim- ple, setaceous antennae, composed of five or six joints, furnished with scattered hairs. They are found in the salt and brackish waters of the sea-coast among the Fuci and Confervae(3). Cypris, Mull. But six feet(4); the two antennae terminated by a bundle of setae resembling a pencil. The shell forms an oval, laterally compressed body, with an arcu- ated and convex back, or towards the hinge; the opposite side is almost straight, and slightly emarginated or reniform. Before the hinge and on the median line is the eye, forming a large, blackish, round point. The intermediate antennae, inserted above, are shorter (1) Desmar., Consid., p. 364. For the other species, seethe same work, p. 361 364, L1V; Mull., Entom-, Cyclops; Jurine, Hist- des Monoc, p. 1 84, prem. fam. des Monoc. a. coquille univalve; Rand., Monoc, I, II, III. (2) It is probable there are but six. See Cypris, note 4. (3) If these Entomostraca inhabit salt-water exclusively, it is easy to see that Jurine and other observers whose geographical position limited their researches to the fresh-water genera, could not have spoken of the former. See Mull., En- tom., Cythere, and Desmar., Consid., p. 387, 388, LV, 8. (4) Four according to Randohr, and eight according to Jurine; the first consi- dering the two last as appendages of the males, and the second looking upon the palpi of the mandibles and the branchial laminae of each upper jaw the two first feet of his second division of the body, those which he says are composed of but one joint and terminated in a dentated spoon as so many feet. The latter does not include in this number those which the former considers a3 sexual organs; he states them p. 161, 166 to be five jointed threads issuing laterally from the pouch of the matrix, of the use of which he is ignorant. BRANCHIOPODA. 123 than the body, setaceous, composed of from seven to eight joints, the last of which are shortest and terminated by a bundle of twelve or fifteen seise, serving as fins. The mouth consists of a carinated labrum, two large dentated mandibles, each furnished with a tri- articulated palpus, to the first segment of which adheres a small branchial leaf with five digitations(l), and of two pairs of jaws. The two superior are much the largest, and have four movable and silky appendages on their internal margin, and a large, pectinated, branchial lamina on their anterior edge; the second are composed of two joints, with a short, nearly conical, inarticulated palpus(2) silky at the end, as is the extremity of the jaws themselves. A sort of compressed sternum fulfils the functions of a lower lip(3). The feet are divided into five joints, the third representing the femur, and the last the tarsus. The two anterior feet, inserted under the antennae, are much shorter than the others, incline forwards, and are furnished with rigid setae, or long hooks united in a bundle at the extremity of the last joints. They are deficient in the four fol- lowing feet. The second, situated in the middle of the under part of the body and at first directed backwards, are arcuated and termi- nated by a long and strong hook inclining forwards. The two last are never visible externally, but are turned up, applied to the poste- rior sides of the body in order to support the ovaries, and terminate in two very small hooks(4). The body presents no distinct articu- lation, and terminates posteriorly in a kind of soft tail which is doubled underneath, with two conical or setaceous threads furnished with three setae or hooks at the end, directed backwards and issu- ing from the shell. The ovaries constitute two large, simple and conical vessels forming a cul-de-sac at their origin, and situated on the posterior sides of the body, underneath the shell, and opening, side by side, in the anterior portion of the abdomen where the canal formed by the tail establishes a communication between them. The ova are spherical. These Crustacea spawn, and change their skin, as frequently as the Cyclopes and other Entomostraca, and their mode of life is the same. Ledermuller states, that he observed them in coitu. Modern naturalists, who have most closely studied them, however, have never been able to discover their sexual organs with certainty, nor been fortunate enough to see them in actu. M. Straus (1) Interior lip, Randohr. (2) Forked in the Ct/pris strigata, Id. (3) Exterior lip, Id. (4) In the figure given by Randohr these feet consist of but three joints, and the last is somewhat dilated and emarginated at the end, with a hook in the middle of the emargination. 124 CRUSTACEA. observed, under the origin of the mandibles, the insertion of a stout conical vessel filled with a gelatinous substance, which appeared to communicate with the oesophagus by a straight canal, that he sus- pects may be a testis or salivary gland. The individuals which were the subjects of these observations having ovaries, the Cy- prides according to the first supposition must be hermaphrodites. This is so much the more doubtful, however, as he himself remarks that it is possible the males may only exist at a particular season of the year, and that the vessel alluded to seems to be more nearly connected with the function of digestion than with that of gene- ration^). According to Jurine, the antennae are true fins, the threads of which are spread out or united at the will of the animal, and in pro- portion to the degree of velocity it wishes to communicate to its motions; sometimes but a single one is visible, at others they are all displayed. We also think that these threads, and those of the two anterior feet, may be considered as aiding in respiration, quite as much as the laminae of the mandibles, and of the two superior jaws, which M. Straus distinguishes by the name of branchial. The last, or those of the jaws, appear to me to be true but greatly dilated palpi, and the two others are appendages of the mandibular palpi. See Jurine, Hist, des Mon. VI, 3. According to the naturalist of Geneva before mentioned, these animals, while they are swimming, move their anterior feet as ra- pidly as their antennae, but very slowly when walking over the sur- face of aquatic plants. These feet, conjointly with the two termi- nated by a long hook, or the penultimates, then support the body. He supposes that those which, according to him, form the second pair, are destined to create an aqueous current and to direct it to- ward the mouth, thereby assimilating their functions to those of the second inferior antennae, which he calls antennulae. The two threads composing the tail unite on leaving the shell, and seem to form but one; they serve, as he supposes, to brush out its interior. The female deposits her ova in mass, fixing them on plants or the mud by means of gluten. During this operation, which lasts about twelve hours, and in the largest species produces twenty-four eggs, she clings with her second feet, and in such a manner as not to fear the shock of the water. He collected some of these packets of newly laid eggs, and after separating them, observed the hatching of the young ones, and obtained a second generation without the in- (1) See the alimentary canal of the Daphnia pulex, figured hy Jurine, X, 7, and Randohr, Monoc, Tab. V, ii, d, d, and x. RRANCHIOPODA. 125 fervention of the males. A female which had deposited her ova on the 12th of April, changed her skin six times hetween that period and the 18th of the following May. On the 27th of the same month she spawned a second time, and two days afterwards, on the 29th, a third. From this, he concludes that the number of these changes in the young animal is in proportion to the gradual deve- lopment of the individual ; that this development can only take place by the general separation of an envelope become too small to contain the animal; and that the size of the latter has a determined limit to which it must.attain(l). The Polyropha of our third division Cladocera, Lat.; Daph- nides, Straus from the second family of the Monoculi of Jurine. The form of two of their antennae, which resemble ramified arms and serve as oars, and the faculty of leaping which they possess, have acquired for one of the most common species, the name of the aquatic arborescent flea. The first of these naturalists, who has given us an excellent mono- graphy of the Daphniae, a subgenus of this division, establishes two new ones; one by the name of Latona, characterized by antennae, in the form of oars, divided into three branches, of but one joint(2); and the other by that of Sida, which approaches other known sub- genera of the same division, in having similar antennae, divided into two branches only, but of which one is composed of two joints, and the other of three(3). The Daphniae, according to him, are distin- guished from the preceding and from the Lyncei, inasmuch as one of the two branches of these oars is composed of three joints and the other of four. Jurine, however Hist, des Mon. p. 92 states, that each branch is composed of three joints; but it seems that he did not include the first of the posterior branch, a very short one, it is true(4). The last, in all these Lophyropha, is terminated by three threads, and each of the preceding ones gives out another; these threads are either simple or barbed. There are also two other but very short antennas particularly in the females situated at (1) See Mull., Entom. genus Cypris; Hist, des Monoc, second dlvis., Mon. a coquilles bivalves, p. 159179, XVII XIX; Rand., Mon., IV; Straus, Mem. du Mus. d'Hist. Nat., VII, 1 ; Desmar., Consid., p. 380386, LV, 17. Desmarest Crust. Foss., XI, 8 has figured a fossil species which he calls Cypris f eve, found in great abundance near the Gergovian mountain in the Puy-de Dome, and between Vichy-Les-Bains and Cussac. (2) Daphnia setifera, Mull., Entom. (3) Daphnia cristallina, Ejusd. Ibid. (4) Randohr has given it in the fig., II, vii, tab. V, of these antennae. 126 CRUSTACEA. the anterior and inferior extremity of the head which have but a single joint with one or two setae at the extremity. In the PoLTrHEMUS, Mull. As in Daphniae and Lynceus, the antennae are in the form of oars divided into two branches; but each of them is composed of five joints. The head, moreover, which is very distinct and rounded, is provided with a sort of neck, and is almost entirely occupied by a large eye. The feet are completely exposed. But a single species has hitherto been discovered, the Mono- culus pediculus, L. ; Deg., Insect., VII, xxviii, 6 13; Polyphe- mus oculus, Mull. , Entom., xx, 1 5; Cephaloculus stagnorum, Lam.; Jurine, Monoc, xv, 1 3; Desmar. , Consid., LIV, 1, 2. The feet, according to Jurine, have no resemblance whatever to the Monoculi of this division. They consist of a thigh, leg, and a tarsus composed of two joints, from the extremity of which, that of the last pair excepted, issue several small threads. Two small antennae, consisting of a single joint and terminated by two threads, project from the anterior extremity of the head. The shell is so extremely diaphanous, that all the viscera can be distinguished. The matrix, when filled with eggs, occupies the greater part of its interior. Their greatest number never exceeds ten. In following the gradual development of the foetus, we are struck with the early appearance of the eye, in comparison with that of other parts of the body. It is greenish at first, and passes insensibly to a deep black. The abdomen, after being flexed from behind forwards, bends sud- denly backwards to form a long, slender, pointed tail, from which issue two long articulated threads. The animal always swims on its back, and most frequently in a horizontal direction, by the quick and repeated motion of its arms and feet, and executes all sorts of evolutions with ease and agility. When young, and after its first changes, it is subject to a disease called the ephippium(l); but this ephippium or saddle always has a determinate figure, and never con- tains the two oval ampullae observed in the Daphniae. These ani- mals do not live long in a state of captivity, nor can their young ones be raised, at least such was the case with Jurine, who could not preserve them after their first changes. Among all the specimens which were the subjects of his observations, he could not find a single male, though, it is true, he could procure but very few of them, this species being rare in the environs of Geneva. It is said, (1) See the following article, Daphnia, p. 128. BRANCHIOPODA. 127 however, to be very common in the marshes and ponds of the North, where it aggregates in considerable numbers. In the Daphnia, Mull. The oars are always exposed to their base or to the origin of their peduncle; they are as long, or almost as long as the body, and are divided into two branches, the posterior of which consists of four joints, the first very short, and the other, or the anterior, of three. Their eye is small or punctiform, and with the exception of certain species, has not, as in Lynceus, the small black punctiform spot be- fore it, which Muller considered as a second eye(l). Although the extreme smallness of these animals might be sup- posed to defy any attempt to investigate their organization, but few are better known. Exclusive of those who have devoted themselves to microscopic researches, four of the most profound naturalists, Schseffer, Randohr, Straus, and Jurine, Sen., the third particularly, have studied them with the most scrupulous attention. If some anatomical details escaped the notice of the latter, the omission has been remedied by the labours of Randohr and Straus; Jurine also completes the observations of the former with respect to their habits, which he studied for a long period, and with the greatest success. The mouth is situated beneath at the base of the rostrum; we con- sider (with Randohr) the inferior portion of the head, which Straus denominates a labrum, as an elongated clypeus, and we apply the for- mer term to that part which he styles the posterior lobule of the labrum. Directly under it are two strong jaws interior jaws of Randohr without palpi, vertically inclined, and applied to two horizontal jaws(2) terminated by three stout horny spines, in the form of recurved hooks. Then come ten feet, the second joint of all of which is vesicular; the first eight terminate by an expansion in the manner of a fin, the edges furnished with setae or barbed threads arranged like a crown or a comb; the two anterior seem to be specially appropriated to the purposes of prehension, and in fact Randohr considers them as double palpi, the external and internal: they are the same parts, elsewhere Cyclops called hands by Jurine. In the figures which they have published, the terminal sets appear to be (1) Such also is the opinion of Randohr, Monoc. pi. V, fig 1 . II, iii, 6; and as he discovered it in the Daphnia sima, it is possible that, although but slightly visible in several species, this character may be common to this subgenus, and that of Lynceus. Schxffer had previously noticed it- (2) The exterior jaws, in the language of Randohr; Jurine not having separated these parts from the preceding ones, supposed that the latter were accompanied by a kind of valve and by a palpus. Hist, des Monoc. IX, f. 13 17. 128 CRUSTACEA. bearded: if this be so, we do not see why these appendages may not concur in the process of respiration( 1), a property confined by Straus to the following ones, because the latter have, besides, a lamina on the inner side, which, with the exception of the two last, is edged with a pectinated series of setae, that according to the figures of Jurine and Randohr are also bearded. The structure of the two last feet is somewhat different, and Randohr distinguishes them by the name of claws. The abdomen, or body properly so called, is divided into eight segments perfectly free between its valves, and is long, slender, recurved at the extremity, and terminated by two small hooks directed backwards. On the superior surface of the sixth segment is a range of four papillae forming indentations, and the fourth presents a sort of tail(2). The ovaries are situated along the sides between this segment and the first, and open separately near the back into a cavity matrix, Jurine formed betwixt the shell and the body, in which the ova remain for some time after they are produced. Midler has given the name of ephippium, or saddle, to a large, obscure, and rectangular spot, which at certain periods, and parti- cularly in summer, appears, after the females have changed their tegument, on the superior part of the valves of the shell, and which he attributes to disease. According to Straus this ephippium pre- sents two oval, diaphanous ampullae, placed one before the other, and forming with those of the opposite side two small oval capsules, opening like that of a bivalve. It is divided, as are also the valves of which it forms a part, into two lateral halves, united by a suture along their superior edge; its interior exhibits another similar, but smaller one, with free edges, provided it be not the superior that is attached to the valves, the two halves of which, playing upon each other as if hinged, present the same ampullae as the exterior lids. Each capsule contains an egg with a greenish and horny shell, other- wise similar to an ordinary ovum, but requiring a greater length of time for its development, and being destined to pass the winter in statu quo. When the animal is about to change its tegument, the ephippium, as well as its ova, is abandoned with the exuviae, of which it constitutes a part, and which protect them during the (1) According to Straus, Cypris and Cythere are not true Branchiopoda, inas- much as their feet are not provided with branchiae; but, as we have already ob- served, the setne and hairs of the two anterior ones and those of the antenna; may exercise the functions of branchiae as well as those of the palpi and first juvvs. (2) We omit various details of the organization, because some can only be com- prehended by means of drawings, and others appear common to most of the Bran- chiopoda. BRANCHIOPODA. 129 winter from the cold. The heat of spring; hatches them, and young Daphniae are produced exactly similar to those which come from the ordinary eggs. Schaeffer affirms that they will remain for a long period in a desiccated state without losing the vitality of the germ, but none of those preserved in that condition by Jurine was ever hatched. They are entirely free, or do not adhere to each other in their peculiar cavities. In summer, according to Jurine, they may be hatched in two or three days. In the climate of Paris, where Straus observed them at all periods of the year, they require at least one hundred hours. The foetus, twenty-four hours after the production of the ovum, is a mere rounded and unformed mass, on which, when closely examined, maybe seen obtuse rudiments of arms in the form of very short and imperfect stumps glued to the body; neither head nor eye is perceptible; and as yet, the green or reddish body dotted with white, like the tgg, exhibits no motion. It is only at the ninetieth hour, and when the eye has appeared, and the arms and valves are elongated, that the fcetus begins to move. By the hun- dredth hour it is very active, and finally, at the hundred and tenth it only differs from the newly hatched animal in the sets of the oars which are still glued to their stem, and in the tail of the valves which is bent under and received between their inferior edges. To- wards the end of the fifth day, the tail, which terminates the valves in the young animal, and the setae of the arms become free, and the feet for the first time begin to move. The young being ready to make their appearance, the mother lowers her abdomen and they dart out. Newly laid eggs deposited in a glass jar, where they were observed by Straus, were developed in this order. Jurine has also furnished us with the result of his analogous observations upon the successive changes in the embryo Daphniae, but made during the win- ter, and as the eggs were not hatched till the tenth day, he could con- sequently detect their development with more precision. The ovum, on the first day, presents a central bubble, surrounded by smaller ones, with coloured molecules in the intervals. These bubbles and mole- cules appear destined to form the organs by approximating towards the centre, and finally disappear. The form of the foetus begins to be defined on the sixth day; on the seventh the head and feet are distinguishable; on the eighth appears the eye as well as the intes- tine; on the ninth the network of that eye begins to be visible, and the bubbles have entirely disappeared, the central one excepted, which contains the alimentary canal under the heart; on the tenth the development of the foetus is terminated, the young Daphnia issues from the matrix and for a moment remains motionless. The males, of those species at least observed by Straus, are very distinct from the females. The head is proportionably shorter; the Vol. III. R 130 CRUSTACEA. rostrum less salient; the valves narrower and less gibbous superiorly, and gaping in front in such a manner as to present a wide and al- most circular opening. The antennae are much larger and have the appearance of being furnished with two horns bent underneath, which are considered by Muller as the organs of generation. Straus could not discover these sexual parts, but he remarks that the little nail terminating the last joint of the two anterior feet or the second, if we suppose the oars to be the first is much larger than those in the female, that it has the form of a very large hook with a strong outward curvature, and that the seta of the third joint is also much longer; it is by means of these hooks that he seizes the female. The mammillae of the sixth segment of the abdomen are much smaller, and at an early age have the form of tubercles. The inferior antennas excepted, which are longest, the two sexes are nearly alike, and the two valves of their shell terminate in a stylet, dentated beneath, arcuated below, and nearly as long as the valves. Every time the animal changes its tegument, this stylet becomes shorter, so that in the adult it forms a mere obtuse point. The males pursue their females with much ardour, and several frequently unite in their advances to the same individual. A single copulation fecundates the female for several successive generations, and for a period of six months, as ascertained by Jurine. Straus, remarking that the orifices of the ovaries are placed very deeply under the valves and that consequently no part of the body of the male could reach them, suspects that he has no copulating organ, but darts the fecundating fluid under the valves of the female, whence it finds its way to the ovaries; analogy however seems to dis- prove this conjecture(l). Jurine saw them in actu, for a period of eight or ten minutes. The male, first placing himself on the back of the female, seizes her with the long threads of his anterior feet; he then seeks the inferior margin of her shell, and approximating the aperture of his own to that of the latter, he introduces the threads, as well as the hooks of these same feet. He now brings his tail in contact with that of his companion, who at first, refusing to comply, flies with her amorous mate, but finally yields. Little granulated bodies of a green, rose, or brown colour, according to the season, gradually ascend into the matrix and become eggs. Jurine observes, that the males of the D. pulex are but few, when compared to the number of femates; that they are extremely rare in spring and sum- mer, but less so in autumn. About the eighth day after they are hatched, the young Daphnia (1) See Jurine, Hist, des Mon. p. 106, et seq. BRANCHIOPODA. ]31 effects its first change of tegument, and repeats the same process every five or six days, according to the increased or diminished temperature of the weather; it is not merely the body and valves which lose their epidermis, the branchiae and setae of the oars under- going the same operation. It is only after the third change that they are fitted to continue their species. At first the female lays but a single eg^, then two or three, gradually augmenting the num- ber, which in the D. magna amounts to fifty-eight. The day after she has produced her ova, the female changes her skin, and in the teguments which she abandons may be found the shells of the eggs she has previously laid. The next moment anew batch is produced. The young from each set of eggs are generally of one sex, and it is rare to find two or three males proceeding from that which produced females, and vice versa. But in five or six of these broods, in the summer, one at most consists of males. Individuals are frequently remarked, whose integuments are of a milky white, opaque and thickened; they do not however appear to be affected by it, and on the renewal of the shell, but slight rugous traces of this alteration are perceptible. These animals cease to propagate, and no longer cast their skins on the approach of winter; they perish before the extreme cold has arrived. The ova contained in the ephippia, and which were laid during the summer, are hatched on the first approach of the vernal heat; and the ponds soon abound again with countless Daphniae. Some naturalists attribute the occasionally sanguine tinge of these waters to the presence of myriads of the D. pulex, but Straus says he never remarked the fact, and that this species is at all times but slightly coloured. Morning and evening, and even during the day in cloudy weather, they keep on the surface; but in the heat of summer, or when the sun darts his rays directly upon the pools which they inha- bit, they descend to the depth of six or eight feet; frequently, not one is to be seen on the surface. Their mode of natation is by little bounds, of a greater or less extent, according to the length of their oars, and in proportion to the projection of the shell which covers the body, an increase of its size impeding their movements. Ac- cording to Straus, their food consists exclusively of small parcels of vegetable substances which they find at the bottom, and frequently of Confervas. They always refused the animal substances he pre- sented to them. He repeatedly saw them swallow their own faeces, carried along by the current formed by the action of their feet, which directs their ordinary aliment towards their mouth. They use the hooks which terminate the extremity of their tail to clean their branchiae. Daphnia pulex; Monoculns pulex, L. ; Pulex aquaticus arbores- 132 CRUSTACEA. cens, Swamm., Bib. Nat., xxxi; Perroquet d'eau, Geoff., Hist. Ins. II, 455; Schsef., Die Griin., arm., Polyp., 1755, I, 1, 8; Straus, Mem. du Mus. d'Hist. Nat. V, xxix, 1 20; Jurine, Mon., viii xi. According to Straus, this species has a large convex rostrum; setae of the oars plumose; first tubercle of the sixth segment linguiform; inferior edge of the valves dentated; valves terminated by a short tail, which is obtuse in the females. This last character distinguishes it from another species with which it has been confounded, the Daph. longispina, Str. Deg. Insect. VII, xxvii, I 4. The female is four millimetres in length(l). The last subgenus of the Lophyropa is Lynceus, Mull. Chilodorus, Leach. It can scarcely be distinguished from the preceding except by the oars, evidently shorter than the shell, the inferior portion of which has but little or no projection. According to Straus the articula- tions of the branchiae are more numerous than in the preceding subgenera. They all have a little spot before their eye which has the appearance of a second one. The rostrum, longer in proportion than that of the Daphniae, is curved and pointed(2). The second section of the Branchiopoda, that of the Phyllopa, is distinguished from the first, as already stated, by the number of feet, which at least amounts to twenty(3) and by the lamellated or foliaceous form of their joints. There are always two eyes, which are sometimes pediculated: several of them have also an ocellus. They form two principal groups. In the first Cehatopthalma, Lat. there are never less than ten pairs of feet, nor more than twenty-two; the vesicular body at their base is wanting; the anterior are never much longer than the others, nor ramified. The body is contained in a shell resembling that of a bivalve, or is naked, each thoracic segment bearing a pair of ex- posed feet. The eyes arc sometimes sessile, small and closely ap- proximated; at others, and most frequently, they are situated at the extremity of two movable pedicles. The ova are internal or external, and are contained in a sac at the base of the tail. (1) For the other species, see Mem. cit. of Straus; Mull., Entom., and Jurine, Hist, des Mon. fam. II, p. 185 58, and p. 181, 200. For the D. sima, and D. longispinu, see Rand., Monc. V VII. (2) See Mull., Entom., G. lynceus; Jurine, Monoc. p. 151, 158; and Desmar., Consid., 375378. (3) These animals represent among the Crustacea, the Myriapoda of the class of Insects. BRANCHIOPODA. 133 Here the eyes are sessile and immovable; the body is invested with an oval shell resembling that of a molluscous bivalve, and the ova- ries are always internal. Such is the Limnadia, Ad. Brong.(l) The Limnadiae are so closely allied to the preceding subgenus, that the only species known was placed among the Daphniae by the younger Hermann. The shell is bivalve, oval, and incloses the body, which is elongated, linear, and inflected forwards. In the head, and almost confounded with it, we find: 1, two eyes closely approxi- mated and placed transversely; 2, four antennae, two of which are much the largest, each composed of a peduncle of eight joints and of two setaceous branches or threads divided into eight segments and somewhat silky; the two others are intermediate, small, simple, and widened at base; 3, the mouth, situated beneath, and consisting of two inflated mandibles arcuated and truncated at the inferior ex- tremity, and of two foliaceous jaws. These parts when united form a sort of inferior rostrum. The body, properly so called, is divided into twenty-three segments, each of which, except the last, bears a pair of branchial feet. All these feet are similar, strongly compress- ed, and bifid; their external division is simple, and ciliated on the exterior edge; the other has four joints, and is strongly ciliated along its interior margin. The first twelve pairs are of equal length, and larger than the others; the length of the latter progressively dimi- nishes. The eleventh pair, and the two following ones, have a slen- der thread at their base, which ascends into the cavity situated be- tween the back and the shell, in order to support the ova. The last segment on the tail is terminated by two threads. The ovaries are internal, and placed along the sides of the intestinal canal, extending from the base of the first pair of feet to the eighteenth; their open- ings appear to be at the root of some of those that are intermediate: The eggs, after having been produced, occupy the dorsal cavity above mentioned, and are secured there by means of small threads, which adhere to those of the feet. At first they are round and trans- parent; they afterwards assume a yellowish tint, which is subse- quently darker towards the centre, and their figure becomes irregu- lar and angular. All the individuals examined by M. Ad. Brongniart were provided with them. The males, allowing the sex to exist, do not appear at (1) In my work on the natural families of the animal kingdom, this subgenus, with that ofJlpus, composes my family of the Aspidiphora; it approximates to this one in the number of feet, and to the Daphnise in the shell. 134 CRUSTACEA. the same time as the females, which is during the month of June, and are unknown. Limnadia Hermani, Ad. Brongn., Mem. du Mus. d'Hist. Nat., VI, xiii; Daphnia-gigas, Herm., Mem. Apterol., V. Found in great numbers in the little pools of the forest of Fontainebleau. There, each eye is situated at the extremity of a pedicle, formed by a lateral prolongation, in the shape of a horn, of each side of the head. The body is naked, without a shell, and annulated throughout. The ova of the females are contained in an elongated capsule, situ- ated near the base of the tail in those which are thus terminated, or in the posterior extremity of the body and thorax in those which have no tail. Some are provided with a tail. Artemia, Leach. Eyes placed on very short pedicles; the head confounded with an oval thorax, furnished with ten pairs of feet, and terminated by a long and pointed tail. The antennae short and subulate. A. salina; Cancer salinus, L. ; Montag., Trans. Lin. Soc. XI, xiv, 8 10; Gammarus salinus, Fab.; Desmar., Consid., p. 393. A small species found in the salt marshes of Lymington, in England, when nearly dry, of which as yet we have but a very imperfect account. Branchipus, Lat. Chirocephalus, B. Prevost, and Jurine. Eyes placed on projecting pedicles; the body narrow, elongated and compressed; the head distinct from the trunk, furnished with appendages varying according to the sex, and with two appendages resembling horns between the eyes; eleven pair of feet; the tail termi- nated by two leaflets more or less elongated and edged with cilia. Although Schaeffer and Benedict Prevost(l) have published very detailed monographs of two species of this genus, they are still imperfect with respect to the profound and comparative study of the organs of the mouth and of some other parts of the head. Con- sidering the two sexes together, we find the following general con- formation; the body is almost filiform, composed of a head separated from the trunk by a kind of neck; of a trunk or thorax longitudinally hollow beneath, divided, at least above, exclusive of the neck, into eleven segments, each bearing a pair of branchial, strongly com- pressed feet, usually composed of three foliaceous joints, with a (1) Mem. sur le Chirocephale printed at the end of the Hist, des Monoc. of the late Lewis Jurine, and previously published in the Journal de Physique. BRANCHIOPODA. 135 fringe of hairs or bearded threads along the edges; and of an elon- gated tail tapering to a point, consisting of nine segments terminated by two more or less elongated leaflets fringed with cilia. Under its second segment we find the male organs of generation, and in the female an elongated sac containing the ova she is ready to produce. In the head we observe, 1. Two reticulated eyes situated at the ex- tremity of two flexible peduncles formed by lateral prolongations of the head; 2. Two antennae at least, frontal, scarcely longer than the head, slender, filiform and composed of very small joints; 3. Two projections under them, sometimes resembling a uniarticulated horn, and at others digitiform the premier doigt des mains, Bened. Pre- vost and biarticulated; 4. A mouth underneath composed of two kinds of dentated mandibles without palpi, and of some other parts. We suspect that these horn-like projections are merely an appen- dage, larger and differently formed in the males, of the frontal an- tennae; the two other antennae may be wanting or be obliterated in the female, and form in the other sex of one of these species Chiro- cephala diaphana, Prevost those singular appendicated and dentated tentacula, in the form of a soft proboscis which is susceptible of being spirally convoluted, designated by Benedict Prevost under the name of doigts des mains, or fingers. It is probable that, as in Apus, the mouth is furnished with two pairs of jaws, a ligula and a labrum, but their respective form and situation have not yet been well ascertained. I am convinced that the part resembling a ros- trum mentioned by Schaeffer, and which Prevost calls a valve (sou- pape) is the labrum; that the four bodies or tubercles placed on the sides, mentioned by the former, are the mandibles and the two upper jaws; and that the parts considered by the second as cirri (barbillons) are also maxillary. The two first feet, which, according to Schaeffer, are composed of but two joints, the last terminating in a point, would represent the two firstfoot-jaws of the Crustacea Decapoda, and the two large antenniform feet of an Apus(l). The chief of the male organs of generation, at least those which are considered as such, consist in two conoid biarticulated bodies, which only project by pressure (Schaeffer), situated under the second ring, in which vessels terminate that arise from the first. M. Prevost presumes that the two vulvae of the female are placed at the extremity of the tail, but that they afford no issue to the ova. This issue (two apertures ac- cording to Schaeffer), is in the second ring, and communicates in- ternally with the sac containing the eggs, which acts as an external (1) See Mem. sur les Anim. sans Verteb., Savign. parti. 136 CRUSTACEA. matrix. But there is no crustaceous animal known in which the female organs of generation are placed at the posterior extremity of the body, and hence we can allow but little weight to this opinion. The observations of Schaeffer on the hairs of the feet of these Crustacea, prove that they are so many air tubes; even the surface of the feet of which they are composed, appears to absorb a portion of the air which adheres to it under the form of little bubbles. The Chirocephalus diaphanus, Bened. Prevost, which seems to us to be very closely allied to our Branchipus palustris, if it be indeed different, has, when first hatched, a body divided into nearly equal and almost globular masses. In the first we ob- serve an ocellus, two short antennae, two very large oars ci- liated at the extremity, and two short, slender feet composed of five joints. After the first change of tegument the two com- pound eyes make their appearance, the body is elongated pos- teriorly, and terminated by a conical, articulated tail with two threads at the extremity. The subsequent changes gradually develope the feet, and the oars disappear. The valve soupape which at first extended over and covered the abdomen, dimi- nishes in proportion. The Branchipi are found, and usually in great numbers, in little muddy, fresh water pools, and frequently in those that are formed by heavy rains, particularly in spring and autumn. On the first ap- proach of cold weather they perish. They swim with the greatest fa- cility on their back, and their feet, which they cannot use for walking, while thus employed, present a graceful and undulating motion. This motion creates a current between them, which, following the canal of the thorax, directs to its mouth the atoms which constitute its- food; when the animal wishes to advance it strikes the water, right and left, with its tail, which forces it forwards by bounds and leaps. Withdrawn from its element, it moves its tail for a while, and curves itself into a circle. Deprived of a certain degree of humidity, it re- mains motionless. Benedict Prevost states, that when the male of the species which constitutes the object of his memoir seeks his female, he swims round her, seizes her by the neck with the two horn-like appendages of his head, and remains fixed there, until she turns up the posterior extremity of her tail, in order to approximate the two valves of the copulating organs; this process is analogous to the coitus of the Li- bellulae. The ova are yellowish, spherical at first, and afterwards an- gular; the shell is thick and hard, a circumstance which lends to preserve them. It appears that even desiccation, provided it be not carried too far, produces no change in the germ, and that the young are hatched as soon as a sufficiency of rain has fallen. M. Desmarest BRANCHIOPODA. 137 has frequently remarked Branchipi in the little hollows filled with rain water, on the summit of the rocks at Fontainebleau. The fe- male Chirocephalus produces several distinct sets of eggs, after each copulation, at different times, occupying some hours and even the whole clay in the process. Each set consists of from one to four hundred eggs; they are rapidly ejected from the female in jets of ten or a dozen, and with sufficient force to sink them slightly in the mud. Benedict Prevost has remarked that the Chir. diaphanus was sub- ject to certain diseases, of which he gives a description. This spe- cies, as we have already stated, does not differ from our Branchipus palustris(l). The two horns, situated under the superior antennae, are composed, in both sexes, of two joints, the last of which, how- ever, is large and arcuated in the male, and very short and conical in the female. In the Branchipus stagnalis(2), the horns consist of a single joint, and those of the males resemble the mandibles of the Lucanus cervus, in their form, dentations, and direction. Others have no tail; their body terminates almost directly behind the thorax and last feet. Such is the Eulimene, Lat. The body of the Eulimenes is almost linear, and has four nearly filiform antennae, two of which are smaller than the others, bear- ing a great resemblance to palpi, and placed on the anterior extre- mity of the head. Their head is transverse, with two eyes seated on large and cylindrical peduncles. There are eleven pairs of bran- chial feet, the three first joints and the last small and tapering; directly after them follows a terminal and nearly semiglobular piece replacing the tail, and from which issues an elongated thread, that, perhaps, is an oviduct. Near the middle of the fifth pair of feet, and of the four following ones, I have remarked a globular body, possibly analogous to the vesicles presented by these organs in the following subgenus. The only species known, Eulimene blanch&tre, Lat., Regne Animal, Cuv., Ill, p. 68; Nouv. Diet. d'Hist. Nat. X, 333; Desmar., Consid. p. 353, 354, is very small; whitish eyes, and (1) Cancer paludosus, Mull. Zool. Dan. XLVIII, 18; Herbst, XXXV, 35; Chirocephalus diaphanus? Prev., Journ. de Phys.; Jurhi., Monoc, XX XXII. See Desmar., Consid. LVI, 2 5. This last species is described in the Manuel du Naturaliste of Duchesne under the name of Marteau d'eau douce. (2) Branchiopoda stagnalis, Lat., Hist, des Crust, et des Ins., IV, p. 297; Can- cer stagnalis, L. ; Gammarus stagnalis, Fab.; Jipus pisciformis, SchaefF. ; Gammarus stagnalis, Herbst., XXX, 310. Vol. III. S 138 CRUSTACEA. posterior extremity of the body blackish. From the vicinity of Nice. The remaining Phyllopa Aspidiphora, Lat. have sixty pairs of feet, all furnished externally near their base with a large oval vesi- cle(l), and the two anterior of which, although much larger and ramous, resemble antennae; a large shell, covering the greater part of the superior portion of the body, almost entirely free, clypeiform, emarginated posteriorly, provided anteriorly in a circumscribed space with three simple, sessile eyes, the two anterior of which are largest and lunated; and two bivalve capsules containing the ova, and annexed to the eleventh pair of feet. Such are the characters which mark the Apus, Scop., Which makes part of the genus Binoculus, Geoff., and of the Li- mulus, Miiller. The body, including the shell, inclines to an oval, wider and more rounded before, and narrowed behind in the manner of a tail; ab- stracting the shell, it is at first nearly cylindrical, convex above, concave and divided longitudinally beneath by a furrow, and termi- nates in an elongated cone. It consists of thirty annuli, which are considerably smaller at the posterior extremity, and which, the last seven or eight excepted, give origin to the feet. The first ten are membranous, soft, without spines, exhibit a small button- like prominence on each side, and have each but a single pair of feet. The others are more solid or horny, with a range of small spines on the posterior margin; the last is larger than the preceding ones, nearly square, depressed, angular, and terminated by two arti- culated threads or setae. In some species composing the genus Lepi- durus, Leach, a horny, flattened and elliptical lamina is seen between them. If the number of feet be about a hundred and twenty, the last annuli, beginning with the eleventh or twelfth, must necessarily have more than one pair, a circumstance which in this respect ap- proximates these Crustacea to the Myriapoda. The shell, perfectly free from its anterior adhesion, invests a great part of the body, and thus protects the primary segments, which, as already stated, are softer than the others. It consists of a large, horny, extremely thin, and almost diaphanous scale or plate, which represents the superior teguments of the head and thorax united, and forming a large, oval, convex shield, angularly notched and dentated at its posterior ex- (1) Possibly analogous to the vesicles forming' the second joint of the feet of the Daphnix. BRANCHIOPODA. 139 tremity. Its upper surface is divided by a transverse line forming two united arcs, in two areas, the anterior nearly semilunar, corres- ponding to the head, and the posterior to the thorax. In the middle of the first, we observe three closely approximated simple eyes, or without apparent facets, the two anterior of which are largest and almost reniform, and the posterior much smaller and oval. A du- plicature of the anterior portion of the shell forms a sort of frontal, flattened, semilunar shield beneath, which serves as a base to the labrum. The posterior area, that which corresponds to the thorax, is carinated throughout the middle of its length. This shell is only adherent by its anterior extremity, so that looking from this point we can discover the whole back of the animal. Each side of the shell, seen from beneath and in a strong light, presents a large spot, formed by numerous lines describing concentric ovals, which appear to be tubular and filled with a red fluid. Directly under the shield or frontal disk, we find the antennae and mouth. The former, two in number, are inserted on each side of the mandibles, are very short and filiform, and are composed of two nearly equal joints. The mouth consists of a square, projecting labrum; of two strong, horny, inferiorly inflated mandibles, compressed and dentated at the extre- mity and without palpi; of a large and profoundly emarginated li- gula; and of two pairs of foliaceous jaws laid on each other, the superior of which are spinous and ciliated along the inner margin, and the inferior almost membranous and similar to small false feet; they are terminated by a slender, elongated joint, and are prolonged externally from their base into a species of auricle, (oreillette) fur- nished with a uniarticulated and ciliated appendage, which may be considered as a kind of palpus. According to Savigny(l), the li- gula exhibits a ciliated canal, which leads directly to the oesophagus. The feet, which amount to about one hundred and twenty, insensibly diminish in size, commencing from the second pair; they are all strongly compressed, foliaceous, and are composed of three joints, exclusive of the two long threads at the extremity of the two ante- rior feet, and the two leaflets at the end of the following ones, parts, which, when united, we may consider as constituting a fourth, for- ceps-like joint, or one with two elongated toes converted into a sort of antenniform threads. On the posterior side of the first joint is inserted a large, branchial, triangular membrane; the second also, on the same side, has a red, vesicular and oval sac. On the oppo- site margin of these feet are four triangular and ciliated leaflets, the superior of which is closely approximated to the toes of the forceps, (1) Mem. sur les Anim. sans Verteb., Savig 1 ., part I, fasc. I. 140 CRUSTACEA. appearing to form a third to the second and following feet, as far as the tenth pair. In proportion as these organs diminish in size, the leaflets approximate more closely, the forceps is more clearly defined and less pointed, and the first toe becomes wider, shorter and rounder. The two anterior feet, which are much larger and are formed like oars, resemble ramous antennas, and have been considered as such by some writers(l): they exhibit four multi-articulated setaceous threads, the two last joints, one of them particularly, being much longer than the others which are situated on the internal side or anteriorly. The two at the extremity are evidently analogous to the toes of the forceps, the remaining two also correspond to as many of the lateral leaflets; it is easy to convince ourselves of this by com- paring these parts in young specimens. After their sixth or seventh change of tegument, the two or three following feet of the latter greatly resemble the two anterior ones, and even their antennas are longer in proportion than in the adult, and are terminated by setse or hairs. The eleventh pair are very remarkable(2). The first joint, behind the vesicles, presents two circular valves, laid one on the other, formed by two leaflets, and containing the ova, which resem- ble granules of a bright red colour. Every specimen which has hitherto been examined being always found to possess this kind of feet, they have been considered as hermaphrodites, and are consi- dered capable of self impregnation. These animals inhabit ditches, pools, stagnant waters, Sec. and usu- ally in myriads. Abducted, when thus assembled, by violent winds, they have been seen to descend in rain. They generally make their appearance in spring, and in the beginning of summer. Their cus- tomary food is the Tadpole. They swim well on their back, and when they sink into the mud they erect their tail. When first pro- duced they have but one eye and four feet, resembling arms or oars, furnished with tufts of hairs, the second of which are the largest. Their remaining organs are regularly developed after each change of tegument. M. Valenciennes, an attache of the Mus. d'Hist. Nat. has remarked that these Crustacea are frequently devoured by the bird vulgarly called the Lavandiere(3). The number of species known being very small, it is unne- (1) They also seem to represent the two first foot-jaws. (2) Schaeffer distinguishes them by the name of uterine feet. The preceding 1 nine pairs, according 1 to his phraseology, form forceps, those of the first oars, or true feet; finally, those which follow the uterine feet, or the twelfth pair and fol- lowing ones, branchial feet. The vesicular sacs lengthen and lessen just as gra- dually; their use is unknown. (3) The Motacilla alba, and cinerea, L. Am. Ed. BRANCHIOPODA. 141 cessary to imitate Leach informing a separate genus Lepidu- rus, Leach for those which have a lamina between the threads of the tail. Such is the Apus prolongatus; Monoculus apus, L.; Schaeff.,Monoc, VI; Limule serricaude, Herm., Jun.; Desmar., Consid. LII, 2. The carina of the shield terminates posteriorly in a small spine, which is not seen in the Apus canciformis; Bi- noclea queue en filet, Geoff., Insect., XXI, 4; Limulus palustris, Mull.; Schaeff., Monoc. I V; Apus vert, Bosc; Desmar., lb., LI, 1; the latter, besides, has no lamina between the caudal threads; it is the type of the genus Apus, Leach, or the Apus properly so called. The same naturalist has figured another species, Apus Montagui, Edinb. Encyclop. Suppl. I, XX. ORDER II. P^CILOPODA. The Psecilopoda are distinguished from the Branchiopoda by the diversity in the form of their feet, among the anterior of which an indeterminate number are ambulatory, or fitted for prehension; while the others, lamelliform or pinnate, are branchial and natatory. It is principally, however, by the absence of the usual mandibles and jaws that they are re- moved from all other Crustacea. Sometimes these parts are replaced by the spinous haunches of the first six pairs of feet ; and sometimes the organs of manducation consist either of an external siphon in the form of an inarticulated rostrum, or of some other apparatus fitted for suction, but concealed or slightly apparent. Their body is almost always, either wholly, or for the greater portion, invested with a shell in the form of a shield, consisting of a single plate in most of them, and of two in others, which always presents two eyes when those organs are distinct. Two of their antennae Cheliceres, Lat. form a forceps in several, and fulfil its functions. Most of them have 142 CRUSTACEA. twelve feet(l), and nearly all the remainder have either ten or twenty-two. Their usual habitat is on aquatic animals, and most commonly on fishes. We divide this order into two families(2). FAMILY I. XYPHOSURA. This family is distinguished from the second by several characters : there is no siphon ; the haunches of the first six pair of feet are covered with small spines and perform the office of jaws ; there are twenty-two feet ; the first ten, with the exception of the two anterior ones in the males, are ter- minated by a didactyle forceps, and inserted, as well as the two that follow, under a large semi-lunar shield ; the latter have the sexual organs attached to them, and the form of large leaflets, as in the case with the ten following, which are bran- chial and inserted under a second shell, terminated by a very hard, ensiform and movable stylet. They are wandering ani- mals, and form the genus Limulus, Fab. The species are known in commerce by the name of the Molucca Crab. The suborbicular, slightly elongated and posteriorly narrow- ed body is divided into two parts, invested by a solid shell com- posed of two pieces, one to each part, very hollow beneath, and pre- senting above, two longitudinal sulci, one on each side, and a carina on the middle of the back. The first part of the shell, or that which covers the fore-part of the body, is much larger than the other, forms an extensive semi-lunar shield, with a reflected edge, furnished above with two oval eyes of numerous facets, resembling granules, one on each side, exterior to a longitudinal carina; and on the anterior ex- (1) Fourteen in several, according 1 to Leach; those which he considers as the two first, however, appear to me to be two inferior antennae. The Arguli, which seem to be the most favoured subgenus with respect to locomotion, have but twelve feet. (2) In my Fam. Nat. du Regne Anim., they form two orders. Pjecilopoda. 143 tremity of the middle one, and common to both pieces of the shell, two small, closely approximated, simple eyes(l); these carinse are armed with teeth or acute tubercles. The duplicature of this shell at its anterior extremity, beneath, forms a level border, strongly arcuated, and terminated inferiorly by a double arc, projecting like a tooth towards the centre of union. Immediately under this pro- jection, in the cavity of the shield, is a small inflated labrum, cari- nated in the middle and terminating in a point, above which are in- serted two little antennae, in the form of small didactyle forceps, flexed into an elbow in the middle of their length, at the point of union be- tween the first joint and the second, or of the forceps properly so styled. Directly beneath, inserted and approximated by pairs, and on two lines, are twelve feet, the ten first of which, the two or four anterior ones of the males excepted, terminate in a didactyle forceps; their radical joint, projecting inwards like a lobe and covered with points, performs the office of a jaw. The size of these feet augments progressively; those of the fifth pair excepted, they are all composed of six joints, the movable toe of the forceps included. The latter have an additional joint, and also differ from the preceding ones by having, at their external base, a bi-articulated appendage, directed backwards, the last joint of which is compressed and obtuse; by their fifth joint being terminated on the inner side by five small, movable, horny, narrow, elongated and pointed leaflets, and by the two toes of the forceps being movable or articulated at base. The two pieces situated between these feet, which M. Savigny considers as the ligula, appear to me to be merely two maxillary lobes of these organs, but detached or free. The pharynx occupies the interval included by all these feet. The males are distinguished from the females by the form of the forceps, which terminate the two or four anterior feet: they are inflated and deprived of the movable toe. The two last feet of this shield are united in the form of a large, mem- branous, and almost semi-circular leaflet, having the sexual organs on its posterior face, and presenting, in the middle of an emargina- tion of the posterior margin, two small triangular, elongated and pointed divisions, which appear to represent the internal toes of the forceps; the other articulations are indicated by sutures. The se- cond piece of the shell, articulated with the first in the middle of its posterior emargination and filling the interval it forms, is nearly triangular, and is angularly truncated and emarginated at its poste- rior extremity. Its lateral edges are alternately emarginated and dentated, and in the middle of each of the emarginations, counting (1) One on each side of the tooth that terminates this carina. 144 CRUSTACEA. from the second, is an elongated and movable spine, six on each side* Inclosed in the inferior cavity, and disposed in pairs on two longitu- nal ranges, are ten fin-like feet, almost similar in form to the two last, but simply united at base, laid one on the other, and bearing, on their posterior face, the branchiae which appear to be composed of numerous and crowded fibres arranged on the same plane one against the other. The anus is situated at the inferior root of the stylet terminating the body. According to an observation communicated to us by M. Straus, we only find in the interior of the first shield, besides the brain, a single sub-oesophagal ganglion(l). The two nervous cords are then prolonged into the interior of the second shield, forming there, and at the origin of the branchial feet, some small ganglia, which send branches to those organs. According to Cuvier, the heart, as in the Stomapoda, is a large vessel furnished internally with fleshy columns, extending along the back, and giving out branches on both sides. A wrinkled oesophagus, ascending in front, leads to a very muscular gizzard, lined with a cartilaginous kind of velvet, studded with tubercles, and followed by a wide and straight intestine. The liver pours its bile into the intestine by two ducts on each side. A great portion of the shell is filled by the ova- ries in the female, and by the testes in the male. These animals are sometimes found two feet in length; they inha- bit the seas of hot climates, and most generally frequent their shores. They appear to me to be proper to the East Indies and the coast of America. The species found in France L. cyclops is commonly called the Casserole{2), from its having some resemblance to the form of that utensil, and because when the feet are removed its shell is used to hold water. Major Le Conte, one of the most intelligent of naturalists in the United States, and who has so largely contributed to advance the science of entomology by his discoveries and re- searches, states that it is given to the hogs. Savages employ the stylet of the tail to point their arrows, which, thus armed, are much dreaded. Their eggs are eaten in China. When these animals walk, their feet are not seen. Fossil specimens are found in certain strata of a moderate antiquity(3). (1) The two anterior feet may represent the mandibles of the Decapoda, the four following ones their jaws, and the last six their foot-jaws; those of the second shield would correspond to the thoracic feet. (2) The King-crab of our fishermen, or the Horse-shoe. Very common on the coast of New Jersey. Am. Ed. (3) Knorr, Monum. of the Deluge, I, pi. XIV; Desmar., Crust, fossil., XI, 6, 7- It would seem from these figures that the lateral spines of the second piece of the PvECILOPODA. 145 In some, the four anterior feet, at least in one of the sexes, are terminated by a single toe. But a single species of this division is known; it is the Limu- lus heteroductylus, and is the type of the genus Tachypleus, Leach(l). I have seen it figured on Chinese vellums. In the others, the two anterior claws at most, are alone monodac- tyle. All the ambulatory feet are didactyle, at least in the females. This division is composed of several species, which, owing to the little attention that has been paid to the detailed form of their parts, to the differences resulting from sex and age, and from their pecu- liar localities, have not yet been characterized in a rigorous and comparative manner. The common American Limulus for instance, when young, is whitish or of a light colour, and has six stout teeth along the whole ridge of the middle of the upper shell, and two others equally strong and pointed on each lateral ridge of the shield or of the first piece of that shell; while older specimens, sometimes more than a foot and a half in length, are of a deep brown colour or almost blackish, their teeth, the middle ones especially, being al- most obliterated. Here also the lateral margins of the second piece of the shell are marked with fine dentations which are scarcely ap- parent or wanting in the former. We should consider as young individuals the Lim. cyclops, Fab., and the L. Soiverbii, Leach, Zool. Miscell., LXXIV; his L. tridentatits, and the L. albns, Bosc: and as older ones, my Limule des Moluques; Monoculus polyphemus, L.; Clus., Exot., lib. VI, cap. xiv, p. 128; Rumph., Mus., XII, a, b, which I at first considered a distinct species, under the belief that these large individuals inhabited those islands exclusively. In all of them, or at all ages, the tail is somewhat shorter than the body, and triangular, the upper ridge finely denticulated and without any decided sulcus beneath. We will designate this species by the name of Limulus polyphemus. These latter characters will distinguish it from some others described by Dr Leach(2). shell, in lieu of spines, merely form smaller teeth articulated at base; but these ar- ticulations have perhaps disappeared. (1) This Limulus is perhaps the Kabutogani or Unkia of the Japanese, and re- presents the constellation of Cancer on their primitive Zodiac. (2) See Nouv. Diet. d'Hist. Nat. Ed. II; Desmar., Consid., p. 344358. Vol. III.T 146 CRUSTACEA. FAMILY II. SIPHONOSTOMA. The Siphonostomse have no kind of jaws whatever. A sucker or siphon, sometimes external and in the form of an acute inarticulated rostrum (1), and at others concealed or but slightly visible, fulfils the functions of a mouth. There are never more than fourteen feet. The shell is very thin and composed of a single piece. They are all parasitical. We will divide this family into two tribes. The first Caligides, Lat. is characterized by the pre- sence of a shell resembling an oval or semi-lunar shield ; by the number of visible feet, which is always twelve, or four- teen, if we include those which Leach considers as such, and which I call inferior antennae ; by the form and size of the tenth pairs which are sometimes multifid, pinnate or ter- minated in a fin, and well adapted at all times and in the adult, for the purposes of natation, and sometimes foliaceous, or broad and membranous. The sides of the thorax are never furnished with wing-like expansions directed backwards and enclosing the body posteriorly. Here, the body, exhibiting several segments above, is elongated and narrowed posteriorly, terminating in a kind of tail with two threads or as many other salient appendages at the end; this extremity is not covered by a segment of the superior teguments in the form of a large rounded scale, deeply notched in the posterior margin. The shell is at (1) The composition of this rostrum or beak is not well known. It is evident, from the figure of the Jlrgulus foliaceus, given by Jurine, Jun., that it contains a sucker; but is this the case with the others, and of how many pieces is it com- posed? I cannot answer the question. I presume, however, that this siphon con- sists of the labrum, mandibles and the ligula which forms the sheath of the sucker. In the preceding Entomostraca, the four anterior feet, whose form is very differ- ent from that of the following ones, would correspond to (he four jaws of the De- capoda. P^,CILOPODA. 147 least half the length of the body. This subdivision will com- prise two genera of Muller. Argulus, Mull. This genus was at first designated under the name of Ozolus, and but very imperfectly described. Jurine, Jun. has since studied its type with the most scrupulous attention, followed it throughout all its changes of age, and produced a perfect and complete monograph of it. He has restored to the genus the original name given by Midler. The Arguli are furnished with an oval shield, posteriorly emargi- nated, covering the body, the posterior extremity of the abdomen excepted, and bearing on a mediate, triangular space distinguished by the name of clypeus, two eyes, four very small, almost cylindri- cal antennae placed in front, the superior of which, shorter and tri- articulated, have a stout, edentated and recurved hook at their base; and the inferior quadriarticulated, with a small tooth on the first joint. The siphon is directed forwards. There are twelve feet. The two first terminate in a transversely annulated disk, striated and edentated along the margin, and presenting internally a sort of rosette formed by the muscles, and apparently acting in the manner of a cup or sucker. Those of the second pair are prehensile, the thighs large and spinous, and the tarsi composed of three joints, the last of which is provided with two hooks. The remaining feet are terminated by a fin formed of two elongated pinnulse, whose edges are fringed with bearded threads: the two first of the latter, or those of the third pair, including the four that precede them, have an ad- ditional but recurved toe. The two last are annexed to that portion of the body which projects posteriorly from the shell, or the tail. The female has but a single oviduct covered by two small feet situ- ated behind the two palettes. The organ which is considered as the penis of the male, is placed at the internal extremity of the preceding joint of the same feet near the origin of the two toes. On the same joint of the two preceding feet, and facing these organs of copula- tion, is a vesicle presumed to be seminal. The abdomen, by which we mean that part of the body which extends posteriorly from the ambulatory feet, the rostrum, and a tubercle containing the heart, is entirely free, without distinct articulations, and terminates directly after the last feet behind, by a sort of tail, in the form of a rounded lamina, deeply emarginated or bilobate, and without terminal hairs: it is a species of fin. The body is so transparent that the heart may be distinguished through its parietes. It is situated behind the base of the siphon, lodged in a solid tubercle, semi-diaphanous and 148 CRUSTACEA. composed of a single ventricle. The blood, formed of little diapha- nous globules, is impelled forwards in a column which soon divides into four branches, two of which proceed directly towards the eyes, and two towards the antennae; the latter are then reflected back- wards and united to the former, constituting a single column on each side, which descends towards the cup, turns round its base, and disappears. A little beneath the two following feet, we may distinguish on each side, another sanguineous column which curves outwards, extends along the borders of the shell, and having reached the two penultimate feet, is flexed forwards and ceases to be visible. Another, where, as in the preceding, the blood flows from the ante- rior part of the body to the posterior, traverses longitudinally the middle of the tail; it unites behind with two other currents that may be seen on the edges of the tail, but which flow in a contrary direc- tion, or appear to return the blood to the heart. Jurine avoids using the term vessel, because the blood which is driven into the anterior part of the body, appears to be diffused there in such a manner, as to induce us to believe that its globules, instead of being contained in particular vessels, are dispersed in the parenchyma of those parts. From what we have stated, however, with respect to the circulation in the Decapoda, it is evident, that the blood, in the first instance, is distributed in the Arguli in the same way, and that the currents or columns of which we have just spoken, seem to indicate the exis- tence of peculiar vessels. This able observer, in fact, subsequently acknowledges that the circulation is not every where carried on in so diffused a manner as in the anterior part of the shell, where, how- ever, in our opinion, it is effectuated as in the Decapoda. The brain, which is situated behind the eyes, appeared to him to be divided into three equal lobes, one anterior and two lateral. The anterior part of the stomach gives origin to two large appendages, each divided into two branches, which ramify in the wings of the shell. The brownish coloured aliment they contain renders these ramifications visible. The caecum is provided near its origin with two vermiform appendages. The excessive ardour of the males frequently induces them to mistake one sex for the other, or to make their advances to preg- nant or dead females. They are placed in coition on their back, to which they cling by means of their feet with cups, for several hours. The period of gestation is from thirteen to nineteen days. The ova are smooth, oval and milk-white. They are fixed with gluten on stones or other indurated bodies, either in a straight line or in two ranges, and from one to four hundred in number; being pressed against each other, their form becomes almost hexagonal. Twenty-ive days after the extrusion of the ova, and after they P^LCILOPODA. 149 have assumed a yellowish and opaque tinge, the eye and parts of the embryo are perceptible. In about ten days more, the shell opens longitudinally, and the tadpole issues from it, being at this period about three-eighths of a line in length. Its general form is similar to that of the adult, but the organs of locomotion present a very essential difference. Miiller has described it in this state by the name of Argulus charon. Four oars or long arms, two situated before the eyes and two behind, each terminated by a pennate and flexible pencil of hairs that have a simultaneous motion, by which the animal is impelled by jerks, project from the anterior extremity of the shell: they do not represent the antennae, for they also are visible. The feet with cups are replaced by two stout feet, flexed into an elbow near the extremity, and terminated by a stong hook, with which it clings to Fishes. The only feet proper to the adult, that are developed and free, are those of the second and third pairs, or the two ambu- latory and the two first natatory feet; the following ones are as yet fixed to the abdomen. The heart, proboscis, and ramifications of the appendages of the stomach are distinct. After the first change of tegument, which is effected by a laceration of its inferior surface, the oars disappear, and all the natatory feet are visible. In three days more the second change ensues, but without producing any important alteration. But after the third, which occurs forty-eight hours subsequently to the second, these same feet are converted into those with cups, still, however, preserving the terminal hook. At the expiration of nine days, there is a new change of skin, and the organs of generation, male and female, are apparent; another change of tegument however is required ere the sexes are fitted for copula- tion, so that the period of their metamorphosis extends to twenty-five days. Still, however, they have attained but the half of their proper size. For that purpose fresh changes of the tegument, which occur every six or seven days, are requisite. Jurine satisfied himself of the fact, that propagation never ensues without the intervention of the male. The females, which he kept separate, perished from a disease which was announced by the appearance of several brown globules, arranged in a semicircle on the posterior portion of the clypeus, and apparently formed in the parenchyma, for they were not dispersed by the change of tegument. Jrgulus foliaceus, Jurine, Jun., Ann. Mus. d'Hist. Nat. VII, xxvi; Monoculus foliaceus, L.; Argulus delphinus, Herm. Jun., Mem. Apter., V, 3, VI, ii; Monoculus gyrini, Cuv., Tabl., Elem. de I'Hist. Nat. des Anim., p. 454; Ozolus gasteroslei, Lat., Hist. Nat. des Crust, et des Insect., IV, xxix, 1 7; Des- mar. , Consid., L. ; Louse of the Stickleback, Baker, Micros., II, xxiv. This species, the only one of the genus that is known, 150 CRUSTACEA. attaches itself to the under part of the body of the tadpoles of Frogs, of that of the Stickleback or Gasterosteus, and sucks its blood. The body is flattened, of a light yellowish green colour, and about two lines and a half in length. Hermann, Jun., who has well described this Argulus in its perfect state, and who quotes a manuscript of Leonard Baldaneur a fisherman of Stras- bourg, dated 1666, in which the same animal is figured, says, that in the environs of that city it is seldom found, except on the Trouts, and that it frequently kills them, those especially which are kept in ponds; it is also found on the Perch, Pike, and Carp. He has never found it on the gills. It has a habit of whirling round like the Gyrini. He says that the body is di- vided into five rings, but slightly distinct on the back. Caligus, Mull. Neither of the feet with cups; those of the anterior pair unguicu- lated; the others divided into a greater or less number of pinnulse or membranous leaflets. A considerable portion of the body is not co- vered by the shell, and is usually terminated posteriorly by two long threads, and sometimes by fin-like or styliform appendages(l). The vulgar name of fish- louse, by which they are collectively de- signated, announces their habits to be similar to those of the Arguli and other Siphonostomse. Several naturalists have considered the tubular threads at the posterior extremity of their body as ovaries; I have sometimes found ova under the posterior and branchial feet, but never in these tubes. Besides, external oviducts thus prolonged are never met with except in females whose eggs are to be deposited in deep holes and cavities now this is not the case with the Caligi. Miiller and other zoologists have remarked that these Crustacea erect and agitate the appendages in question. We believe with Ju- rine, Jun., and such also is the opinion of his father, that they serve for respiration, like the terminal filaments of the abdomen of an Apus(2). (1) The interval also frequently exhibits other, but smaller or much less salient appendages. (2) In the Ann. Gner. des Sc. Phys., vol. HI, p. 343, Brussels, is an extract from the observations of Dr Surriray on the foetus of a species of Caligus which he believes to be the elongatus, and which is very common on the operculum of the Esox belone. That gentleman informs us that by pressing the two caudal threads of the animal in question, a number of transparent and membranous ova were ex- truded, each of which contained a living foetus, very different from the mother, and of which he gives a description. From these observations we might be in- duced to conclude that these threads are a kind of external oviducts: but is there PvECILOPODA. 151 Some of them whose feet are free, and (the two last excepted) annexed to the anterior part of the body Cephalothorax, Lat. covered by the shield, in which some of the posterior feet are fur- nished with numerous and pennated threads, and in which the si- phon is not apparent, have the abdomen naked above and termi- nated by two long threads, or as many stylets; they compose the subgenus Caligus, properly so called. Caligus risculus, Leach(l). In all others, the superior surface of the body is imbricated, or that portion of the body is enclosed in a kind of case formed by the last feet which resemble membranes and fold over it. Of these latter, there are some whose antennae never project like little claws, whose feet are free, and whose last ones do not envelope the body like a membranous case. They form the following sub- genera. Pterygopoda, Lat. Nogaus? Leach. Where the posterior extremity of the body is terminated by two kinds of fins: where the under part of the post-abdomen or of the second division of the body, not covered by the shield, is furnished with pinnated or digitated feet; and where there is a distinct pro- boscis or rostrum(2). Pandarus, Leach. Two threads at the posterior extremity of the body; the first and fifth pairs of feet unguiculated, and the remainder digitated; no ap- parent siphon(3). Dinemoura, Lat. Two long anal filaments and an apparent siphon; the two anterior feet unguiculated; the two following ones terminated by two long toes, and the remainder membranous leaflets(l). no mistake in this ? I have studied these same organs in various specimens pre- served in spirits, it is true but could never discover any body whatever. (1) Caligus piscinus, Lat.; Cal.curtus, Mull. Entom., XXI, 1, 2; Monoculus pis- cinus, L. ; Cal. Mullen, Leach; Desmar., Consid., L, 4; found on the Cod. The Oniscus lutosus, Slabber, Encyclop. Method., Atl. d'Hist. Nat. CCCXXX, 7, 8, from the fin-like appendages of its tail, seems to indicate a separate subgenus. The Binocle a queue enplumet, Geoff., might be placed in it. (2) A single living species found on the Shark. See the genus Nogaus, Des- mar., Consid., p. 340. (3) Pandarus bicolor, Leach; Desmar., L, 5; Pandarus Boscii, Leach, Encyc. Brit. Suppl. I, xx. For the other species, see Desmar., lb., p. 339. (1) Caligus productus, Mull., Entom. XXXI, 3,4; Monoculus salmoneus, Fab. 152 CRUSTACEA. The last subgenus of this subdivision, that of Anthosoma, Leach, Approximates to Dinemoura in the presence of a siphon, and in the two caudal threads; but it is removed from it, as well as the preceding ones by its projecting antennae which resemble little mo- nodactyle claws, and by its six last feet which are membranous, united inferiorly, and folded laterally over the post-abdomen, en- veloping it like a case; those of the first and third pairs are ungui- culated; the second feet are terminated by two short and obtuse toes(2). There, the body is oval, without salient caudiform appendages, composed of threads or fin-like productions at its posterior extre- mity. A portion of the superior teguments forms a shield, which does not cover its anterior half, is rounded and emarginated before, widened and as if bilobate behind; then follow three pieces or scales, posteriorly rounded and emarginated, the second of which, and the smallest of the three, is almost in the form of a reversed heart; the last, and the largest, is arched. The four posterior feet are in the form of laminae, and are united by pairs; those of the first and the third are unguiculated; the extremity of the second is bifid. The siphon is apparent. The ova are covered by two large, oval, conti- guous, coriaceous pieces, placed under the abdomen, and surpassing it in length. Such are the characters of the genus Cecrops, Leach, Of which a single species only is known. Cecrops Latreillii, Leach, Encyc. Brit.,Supp. I, xx; 1, 3, the male; 2, 4, the female; 5, the antennae magnified; Desmar., Con- sid. L, 2. Found on the branchiae of the Tunny and Turbot. The second tribe, that of the Lerneiformes, Lat., consists of Entomostraca, which approximate to the Lernese, in their external configuration, still more than the preceding subge- nera. There are but ten feet visible(3), mostly very short, and but slightly or nowise adapted to natation. Sometimes the body is nearly vermiform and cylindrical, the anterior (2) Anthosoma Smithii, Leach; Desmar., Consid., L, 3; Caligus imbricatus, Risso. (3) There are probably two more, as in the preceding- subgenera, but they are either indistinct or have such a peculiar form that they have not been recog-nized. PjECilopoda. 153 segment being merely somewhat widened and furnished with two projecting didactyle claws; sometimes, on account of two lateral expansions resembling lobes or wings behind the thorax, and of two posterior ovaries, it forms a small quadrilateral mass. This tribe is composed of two genera. In the first or the Dichelestium, Herm., Jun. We observe a narrow elongated body, slightly dilated before, and composed of seven segments, the anterior of which the thorax of Herm. is wider than the others, rhomboidal, and formed of the head and a portion of the thorax united. It bears: 1, four short an- tennae, of which the lateral are filiform and consist of several joints, and the intermediate project like little arms and are quadri-articu- lated, the last joint terminating in a didactyle claw; 2, an inferior, membranous, and tubular siphon; 3, three kinds of deformed palpi two multifid feet? on each side, placed on an eminence; 4, four pre- hensile feet, the two first of which consist of a thigh and leg ter- minated by various unequal and dentated hooks, and the others of an enlarged thigh terminated by a small but stout nail. The second and third segments are almost lunulated, each bearing a pair of feet formed of a single joint, terminated by two kinds of toes, dentated at the end. To the fourth segment is attached another pair of feet, the fifth and last, but having the form of simple, oval, divergent, and immovable vesicles, which Hermann presumes are rather ovaries than feet. This segment, as well as the next, is nearly square. The sixth is much longer, and cylindrical. The seventh and last is three times shorter, almost orbicular, flattened and terminated by two small vesicles. The eyes are not distinct. Dichelestium sturionis, Herm., Jun. Mem. Apter. p. 125, V, 7, 8; Desmar., Consid. L, v. About seven lines long and one broad. The second segment is prolonged on each side into an obtuse papilla, and the four following are red in the middle, with whitish-yellow along the lateral margins. When viewed from above, the feet are not visible. This animal penetrates deeply into the skin and places itself on the osseous arches of the branchiae, but without, as it appears, intruding upon their combs. Twelve of them were taken by Hermann from a single fish. Of this number, two or three, perhaps males, were one third shorter than the others, and had a curved body; one of the twelve lived three days. They are constantly whirling about, and with considerable vivacity. By means of their frontal claw3 they are enabled to cling with great tenacity. Vol. III. U 154 CRUSTACEA. Nicothoe, Aud. and Edw. These animals terminate the Crustacea, and are distinguished from all others of that class by their heteroclitical form. To the naked eye they seem nothing more than two lobes united in the form of a horse-shoe, which enclose two others. By the aid of glasses, how- ever, we discover that the two large lobes are formed by the great expansion of the sides of the thorax, which resemble wings, are almost oval and thrown behind ; that the two others are external ovaries or clusters of eggs, analogous to those of a female Cyclops, and inserted, one on each side, into the base of the abdomen by means of a short pedicle; and that the body of the animal is com- posed of the following parts: 1, a distinct head furnished with two separate eyes; two short, setaceous, lateral antennae formed of ele- ven joints, each with a hair on the inner side; a mouth forming a circular aperture which acts as a cup, and accompanied on each side with anterior feet maxilliform appendages; 2, a thorax of four segments, with five pairs of feet beneath, the two anterior of which are terminated by a stout hook, and are bidentated on the inner side; the remaining eight being formed of one large joint, terminated by two nearly equal and cylindrical stems, each composed of three joints, and furnished with setae: 3, a pointed abdomen of five annuli, the first and largest of which gives origin to the oviferous sacs; the last is terminated by two long hairs. The lateral expansion merely appears to be an excessive development of the fourth and last ring of the thorax. Within we may perceive two kinds of entrails origi- nating from the median line of the body, which may be considered as caeca or divisions of the intestinal canal in a state of hernia. They are endowed with a very decided peristaltic motion. We have seen that the stomach of the Arguli also exhibits two caeca, which ramify in the wings of their shell, and it is possible that these thoracic ex- pansions of the Nicothoes may be two analogous lobes(l). Nicothoe astaci, Aud. and Edw. Ann. des Sc. Nat., 1826, XLIX, 1, 9. The only species known; it is about half a line long and three lines broad, the thoracic enlargement included. It is rose-coloured, paler on the oviferous sacs; the expansions yellowish. It adheres closely to the branchiae of the Lobster, and penetrates deeply between the filaments of those organs. It is only found in small numbers, and on a few individuals. All the Nicothoes observed by these two naturalists were furnished with ovaries; it is probable that previously to fixing themselves U) In this case, the genus may be approximated to the preceding 1 one. PjECilopoda. 155 on the branchiae of the Lobster, and before their thoracic lobes have acquired their ordinary development, they can swim; that development, as is the case with the body of the Ixodes, may be the result of superabundant nutrition. TRILOBITES. According toBrongniartand various other naturalists, it is in the vicinity of the Limuli and other Entomostraca with numerous feet, that we should place these singular fossil ani- mals, originally confounded under the common name of Ento- molithus paradoxus, and now designated by that of Trilobites, of which an excellent monograph, enriched with good litho- graphic figures, has been published by that gentleman(l ). By this hypothesis we have to admit as a positive or at least highly probable fact, the existence of locomotive organs, al- though, notwithstanding the most careful investigation, no vestige of them has been discovered(2). Presuming, on the contrary, that these animals were deprived of them, I thought that their natural position was in the neighbourhood of the Chitones, or rather that they constituted the original stock of the Articulata, being connected on the one hand with these latter Mollusca, and on the other with those first mentioned, and even with the Glomeres(3), to which some Trilobites, (1) M. Eudes Deslongchamps, professor of the University of Caen, Count Ra- soumowski, M. Dalman and other savans have since published new observations on these fossils. M. Victor Audouin, zealously advocating the opinion of Brong- niart, has contested that published by me, in which I approximate them to Chiton. The great difficulty was to prove the existence of feet, and this he has not done. The application of his theory of the thorax of Insects to the Trilobites, appears to me so much the more doubtful, as, according to my view of the matter, the first annuli of the abdomen of Insects alone represent the thorax of the Crustacea De- capoda. (2) M. Parkinson (Outlines of Oryctology) thinks he has perceived them, and suspeats that they are unguiculated. See also the Entomostracite granuleux Brongn., Trilob., Ill, 6, Ann. des Sc. Nat. tome XV. (3) First edition of the Regne Animal, tome III, p. 150, 151. There is no Branchiopoda known which can contract itself into the form of a ball. This cha- racter is peculiar to Typhis, Sphxroma, Tylos, and Armadillo among the Cms- tacea; and among the class of apterous Insects to Glomeris, a genus which is at the 156 CRUSTACEA. such as the Calymenes, appear to approximate, as well as to the Chitones, inasmuch as by contracting they could also be- come spherical. Since the publication of M. Brongniart's work, some naturalists have rejected his opinions and adopted mine, either wholly or in part; others still hesitate. Be this as it may, these animals appear to have been annihilated by some ancient revolution of our planet. The Trilobites, one heteromorphous genus excepted, that of Agnostus, have, like the Limuli, a large anterior segment in the form of an almost semicircular or lunated shield, fol- lowed by from about twelve to twenty-two segments(l), all transversal except the last, and divided by two longitudinal sulci into three ranges of parts or lobes, whence their name of Trilobites(2). Some naturalists call them Entomostracites. head of that class, and which leaves between it and the latter Crustacea a consi- derable hiatus. The Calymenes, with respect to this contractility, evidently ap- proach these latter Insects, the Typhes and Sphseromx; but it does not appear that the posterior extremity of their body is provided with lateral natatory appen- dages, a negative character which would remove them from the Sphxromx, but approximate them to Armadillo, and particularly to Tylos, where the superior part of the thoracic segments is divided into three. The study of a well pre- served specimen has convinced me that, like the Limuli, they had eyes placed against two prominences, and that the cornea was granulous or with facets. The non-existence of the superior antenna also indicates a new affinity between these same Trilobites and the Limuli. (1) The body of various Trilobites, and particularly of the Asaphi, seems to consist, exclusive of the shield, of twelve segments, well separated on the sides, and of another forming the post-abdomen, or a triangular or semi-lunar tail, whose divisions are superficial and do not cut its edges. In the Paradoxides, on the contrary, the lateral lobes terminate by well marked acute prolongations, and twenty -two of them can be distinctly counted. A species of Trilobite, men- tioned by Count Rasoumowski in his memoir on fossils, Ann. des Sc. Nat. June, 1826, pi. xxviii, ii, which he presumes should constitute a new genus, is, in this respect, very remarkable. Its lateral lobes form very long thongs or slips taper- ing to a point. The feet of the pups of the Culices are elongated, flattened, inarticulated laminae terminated by threads and folded on the sides. They are in a rudimental state, and may be analogous to the lateral divisions of this species of Trilobite, allied to the Paradoxides. (2) The Squillx, and various Amphipodous and Isopodous Crustacea have also several of their segments trisected by two impressed and longitudinal lines; but these lines are nearer to the edges and do not form deep sulci. p^ecilopoda. 157 Agnostus, Brongn. The only genus where the body is semicircular or reniform. In all the other genera it is oval or elliptical, and exhibits the general cha- racters above mentioned. Calymene, Brongn. The Calymenes are distinguished from all other Trilobites, by the faculty of contracting their body into a ball, and in the same manner as Sphaeroma, Armadillo, and Glomeris, that is, by approximating the two inferior extremities of the body. The shield, as broad as it is long, or broader, is furnished, as in the Asaphi and Ogygiae, with two oculiform prominences. The segments do not project beyond the sides of the body, and are united throughout; the body is termi- nated posteriorly by a sort of triangular and elongated tail. In Asaphus, Brongn. The oculiform tubercles seem to exhibit a sort of eye-lid, or are granulous; the species of tail which terminates the body posteriorly, is less elongated than in Calymene, and is either nearly semicircular, or in the form of a short triangle(l). In the Ogygia, Brongn. The shield is longer than it is broad; its posterior angles are extended into a kind of spine. The oculiform tubercles exhibit neither eye- lid nor granulations. The body is elliptical. Paradoxides, Brongn. The eye-like tubercles cease to exist, or are not apparent in this genus. The segments, or at least most of them, project beyond the sides of the body, and are free at their lateral extremity. Such are the characters of the five genera established by M. Alex- ander Brongniart, which may be arranged in three principal groups: the Reniformes Agnostus; the Contractiles Calymene; and the Exttnsi Asaphus, Ogygia and Paradoxides. (1) In the Asaphus Brongniarti, described and figured by M. E. Deslongchamps, the posterior angles of the shield, instead of being directed backwards as in the other species, are recurved. 158 CRUSTACEA. For a description of the species and their localities, we refer the reader to the excellent work of this celebrated naturalist, who in his labours upon the fossil Crustacea, properly so called, or universally admitted as such, has availed himself of the talents of one of his most distinguished pupils, M. Desmarest, frequently referred to by us, not only with respect to this particular part of the science, but in relation to his work on the living Crustacea. Different naturalists have proposed various generic sections of these fossils; but being restricted to general considerations, I have adopted those presented to us by the best work hitherto produced on the subject. 159 CLASS II. ARACHNIDES. The Arachnides, which compose the second class of articu- lated animals provided with movable feet, are, as well as the Crustacea, deprived of wings, are not subject to changes of form or do not experience any metamorphosis, simply casting their skin. Their sexual organs also are at a distance from the posterior extremity of the body, and situated at the base of the abdomen, those of several males excepted : but they differ from them as well as from Insects in several particulars. Like the latter, the surface of their body presents apertures or transverse fissures called stigmata(l), for the introduction of air, but they are few in number eight at most, and usually but two and confined to the inferior portion of the abdomen. Respiration is also effected either by means of air-branchiae, fulfilling the functions of lungs, that are contained in sacs of which these stigmata are the apertures, or by radiated tra- cheae(2). The visual organs merely consist of ocelli, which, when numerous, are variously grouped. The head-, usually confounded with the thorax, in place of the antennse, has two articulated pieces in the form of small didactyle or mo* nodactyle chelae, improperly compared to the mandibles of Insects, and so denominated, moving in a contrary direction to the former, or from above downwards, still however co- operating in the business of manducation, and replaced in (1) A vague and improper appellation, for which we might substitute pneumos- toma, air-mouth, or spiraculum. (2) See general observations on Insects. 160 ARACHNIDES. the Arachnides, where the mouth has the form of a siphon or sucker, by two pointed blades which act as lancets(l). A kind of lip labium, Fab. or rather ligula, produced by a pectoral prolongation; two jaws formed by the radical joint of the first segment of two small legs or palpi(2), or by an ap- pendage or lobe of that same joint ; a part concealed under the mandibles, called langue sternale by Savigny descrip- tion and figure of the Phalangium copticum and composed of a projection in the form of a rostrum, produced by the union of a very small clypeus terminated by an extremely small tri- angular labrum, and of an inferior longitudinal carina, usually very hairy, are the parts, which, with the pieces termed mandibles, constitute with some modifications the mouth of most of the Arachnides. The pharynx(3) is placed before a sternal projection which has been considered as a lip, but which, from being placed directly behind the pharynx and having no palpi, is rather a ligula. The legs, like those of (1) Chelicerse, or forceps-antennm: the evident result of the comparison between them and the intermediate antenns of various Crustacea, those of the Psecilopoda particularly. It cannot then be said, strictly speaking 1 , that the Arachnides are deprived of antennae, a negative character, which, previous to us, had been ex- clusively attributed to them. (2) They only differ from legs properly so called, by their tarsi, which are composed of a single joint, and are usually terminated by a small hook, resem- bling, in a word, the ordinary feet of the Crustacea. See our general observa- tions on the first order. These jaws and palpi appear to correspond to the pal- pigerous mandibles of the Decapoda and to the two anterior feet of the Limuli. In Phalangium, the four following legs have a maxillary appendage at their origin, so that these four appendages are analogous to the four jaws of the preceding animals. I had described these parts, long before the publication of Savigny's memoirs on the invertebrate animals, in a monograph of the species of this genus proper to France. From these and the preceding observations it is evi- dent that the composition of these animals is easily reduced to the same general type which characterizes all articulated animals with articulated feet. The Arach- nides are not then a sort of acephalous Crustacea, as stated by this savant, usually so exact in his anatomical observations, of which, unfortunately for the sciences, he has become the victim. (3) Although Savigny admits of two orifices, neither Straus nor myself can find but one; it must have been the effect of an optical illusion, arising from the fact of his having only perceived the lateral extremities of the fissure, its middle being concealed by the tongue with which its anterior face is thickened in its mediate portion. ARACHNIDES. 161 insects, are commonly terminated by two hooks, and even sometimes by one more, and are all annexed to the thorax, or rather cephalo-thorax, which, except in a small number, is only formed of a single segment and is frequently intimately united to the abdomen. This latter part of the body is soft, or but slightly defended, in most of them. With respect to their nervous system, the Arachnides are greatly removed from the Crustacea and Insects; for if we ex- cept the Scorpions, which from the knots or joints forming their tail have some additional ganglions, the number of these enlargements of the two nervous cords is never more than three, and even in the latter, all counted, it never extends beyond seven. Most of the Arachnides feed on Insects which they either seize alive, or to which they adhere, abstracting their fluids by suction. Others are parasitical, and live on vertebrated animals. Some of them however are only found in flour, on cheese, and even on various vegetables. Those which live on other animals frequently multiply there to a great extent. Two of the legs, in some species, are only developed by a change of the tegument, and in general it is not until the fourth or fifth change of skin that these animals are capable of pro- pagation^). Division of the Arachnides into orders. Some have pulmonary sacs(2), a heart with yery distinct vessels, and six or eight simple eyes. They compose our first order, or that of the Pulmonari^e. The others respire by tracheae, and have no organs of cir- (1) We have seen, according to the observations of Jurine, Jun., that they only acquire this faculty after their sixth change. This fact is also applicable to the Lepidoptera, and probably to other insects that frequently cast their skin, for caterpillars usually change it four times before they enter into the state of a chry- salis which is a fifth. The insect does not become perfect until after another, so that it changes its skin six times. (2) Sacs containing air-branchise, or fulfilling the functions of lungs, and distin- guished by me from the latter by the name of pneumo-branchix. Vol. Ill V 162 ARACHNIDES. dilation, or if they have, the circulation is not complete. The tracheae are divided near their origin into various branches, and do not, as in Insects, form two trunks which run parallel to each other throughout the whole length of the body and receive air from various points by means of numerous stigmata. Here, but two, at most, are distinctly visible, and they are situated near the base of the abdomen(l). The number of simple eyes is at most but four. They constitute our second and last order, or that of the Tracheari^e. ORDER I. PULMONARIiE(2). We here find a well marked circulating system and pulmo- nary sacs, always placed under the abdomen, announced ex- ternally by transverse openings or fissures (stigmata), of which there are sometimes eight, four on each side, and at others four, or even two. The number of simple eyes is from six to eight(3), while in the following order it never exceeds four, and is most generally but two ; sometimes they are hardly per- ceptible, or even annihilated. The organ of respiration is formed of little laminae. The heart is a large vessel which (1) The Pycnogonides exhibit no stigmata, and seem, in this respect, to approach the last of the Crustacea, such as Dichelestium, Cecrops, and other Siphonostomous Entomostraca. Savigny thinks they have a closer affinity to the Lsemodipoda, from which, however, they are greatly removed, by the organization of the mouth as well as by their eyes audjfeet. We still believe, however, from the en- semble of their characters, that tlggy rather belong to the class of Arachnides, and that they approximate particularly to Phalangkim with javhich various authors have arranged them. We also think that they may respireby the surface of their skin. At all events, we must await the results of anatomical investigation, be- fore we can decide. (2) Usogata, Fab. (3) The Tessarops of Kafin., according to him, has but four eyes; I presume, however, that the lateral ones escaped his notice. See the subgenus Eresus. pulmonary. 163 extends along the back, and gives off branches on each side and anteriorly(l). There are always eight legs. The head is always confounded with the thorax, and presents at its anterior superior extremity two mandibles so called by authors, the chelic.erse or antennc-pinces, Latr. terminated by two fingers, one of which is movable, or by a single one resembling a hook or claw that is always movable(2). The mouth is composed of a labrum(3), of two palpi, sometimes resembling arms or claws, of tlfe two or four jaws, formed, when there are but two, by the radical joint of these palpi, and moreover, when there are four, by the same joint of the first pair of feet, and of a ligula consisting of one or two pieces(4). If we base our arrangement on the progressive decrease of the number of pulmonary sacs and stigmata, the Scorpions' where it is eight, while in the other Arachnides it amounts to but four or two, should form the first genus of this class, and consequently our family of the Pedipalpi should precede that of the Araneides(o). But the latter Arachnides (1) According to Marselde Serres,Memoire surle Vaisseau Dorsale deslnsectes, the blood, in the Araneides and Scorpions, is first directed to the organs of respira- tion, and thence proceeds to various parts of the body through particular vessels. Judging, however, from the affinity of these animals to the Crustacea, the circula- tion would seem to be effected in the contrary direction. See the Memoir of Treviranus on the Anatomy of Spiders and Scorpions. (2) These parts are formed of a first very large and ventricose joint, one of whose superior angles, when the chelae are didactyle, forms the fixed finger, and of a second joint, that which forms the opposite and movable finger or the hook, when there is but one finger. In the latter case, as with several of the Crustacea, I will employ the term claw. (3) See our general observations on the class. (4) That of the Scorpions appears to be composed of four pieces, forming an, elongated and pointed triangle, directed forwards; the two lateral ones however are evidently formed by the first joint of the two anterior feet, and may be con- sidered as two jaws analogous to the first. We see by Mygale, Scorpio, &c. that the palpi are divided into six joints, of which, in the other Araneides, the first or radical one, is anteriorly and internally dilated to form the maxilliform lobe. Even this lobe, in some species, is articulated at base, and thus becomes a maxillary appendage of this same joint. Exclusive of this joint, the palpus consists of but five, and such is the most usual mode of supputation. In the Scorpions the movable finger of the forceps, as in that of the Crustacea, forms the sixth joint. (5) In my Fam. Nat. du Regne Animal, I begin with the Pedipalpi. M. Leon Dufour also thinks that the Scorpions should come first. 164 ARACHNIDES. are in a manner insulated by their male organs of generation, by the claw or hook of their frontal mandibles, by their pedi- culated abdomen and its spinning apparatus, and by their habits; besides this, the Scorpions appear to form a natural transition from the Arachnides Pulmonariae to the family of the Pseudo-Scorpiones, or the first of the following order. We will therefore commence, as we have said, with the Araneides or spinners. FAMILY I. ARANEIDES. This family is composed of the genus Aranea, Lin., or the Spiders. They have palpi resembling little feet, without a forceps at the end, terminated at most in the females by a lit- tle hook, and the first joint of which, in the males, gives ori- gin to various and more or less complicated sexual appen- dages^). Their frontal chelicerse (the mandibles of authors) are terminated by a movable hook, flexed inferiorly, under- neath which, and near its extremity, which is always pointed, is a little opening, that allows a passage to a venomous fluid contained in a gland of the preceding joint. There are never more than two jaws. The ligula consists of a single piece, is always external and situated between the jaws, and either more or less square, triangular or semicircular. The thorax(2) usually marked with a depression in the form of a V, indicating the space occupied by the head, consists of a single segment, (1) From all the observations that have been made on the mode of copulation of the Araneides, I am still inclined to believe that these appendages are the genital organs. I have vainly sought for particular organs on the base of the abdomen of a large male Mygale preserved in spirits. We are not always to judge from analogy; for the sexual organs in the female Glomeris, Julu^, and other Chilognatha, are situated near the mouth, a fact of which no second exam- ple is to be found. (2) The term cephalo-thorax, would be more strict and proper; not being in use, however, I have thought it best to avoid it; neither will I employ that of corselet, although generally admitted, because, with respect to the Coleoptera, Orthoptera, he. it only applies to the prothorax or first thoracic segment. I'UL&IONARIJE. 165 posteriorly to which, by means of a short pedicle, is suspended a movable and usually soft abdomen; it is always furnished, under the anus, with from four to six closely approximated cylindrical or conical, articulated mammillae with fleshy ex- tremities, which are perforated with numberless small ori- fices(l) for the passage of silky filaments of extreme tenuity proceeding from internal reservoirs. The legs, identical as to form, but of different sizes, are composed of seven joints, of which the two first form the hip, the third the thigh, the fourth(2) and fifth the tibia, and the two others the tarsus: the last is terminated by two hooks usually pectinated, and in se- veral by one more, which is smaller and not dentated. The intestinal canal is straight, consisting of a first stomach com- posed of several sacs, and then of a second stomach or dilata- tion surrounded with silk. According to the observations of M. Leon Dufour Ann. des Sc. Phys. VI it occupies the greater part of the abdominal cavity, and is immediately en- veloped by the skin. It is of a pulpy consistence, and is form- ed of granules(3), whose individual excretory ducts unite in several hepatic canals, which pour the secreted matter into the alimentary tube. In the middle of its superior surface is a depressed line, where the heart is lodged, and which di- vides that organ into two equal lobes. Its form, like that of the abdomen, varies according to the species; thus in the Epeira sericea its contour is festooned. In this subgenus, as in the Lycosa tarentula, its surface is covered with a whitish coat split into areolae, which, in several species, are easily perceived through the glabrous skin ; they may be seen obey- ing the impulse communicated to them by the systole and (1) These holes are pierced in the last segment, which is frequently retracted. If it be strongly compressed, very small mammilla, (at least in some species,) per- forated at the extremity, are protruded they are the true fusi or spinning 1 appa- ratus. Some naturalists think that the two smaller mammillae, situated in the middle of the four exterior ones, furnish no silk. (2) This joint or the first of the tibia is a kind of patella. (3) The liver of the Scorpions is composed of pyramidal and fasciculated lobules, a circumstance which seem* to announce a more advanced degree of organization. 166 ARACHNIDES. diastole of the heart, Both sexes frequently eject from the anus an excrementitious fluid, part of which is milk-white, and the remainder black as ink. The nervous system is composed of a double cord occupy- ing the median line of the body, and of .ganglions which dis- tribute nerves to the various organs. M. Dufour has not been able to determine the number and disposition of these gang- lions, but from the figure of this system given by Treviranus - Veber deninnern, bau des Arachniden, tab. V, fig. 45 there are but two. The observations of the latter will also supply the want of those relative to the organ of the circulation by M. Dufour, which, according to him, appears to consist of a simple dorsal vessel, as well as with respect to the testes and spermatic vessels, on which he is totally silent. The dorsal region of the abdomen in several Araneides, those especially which are glabrous or but slightly pilose, ex- hibits depressed points varying both in number and arrange- ment. M. Dufour has ascertained that these little orbicular depressions are caused by the insertion of filiform muscles, which traverse the liver, and which he has also observed in the Scorpions. The one or two pairs of pulmonary sacs are indicated exter- nally by as many yellowish or whitish spots near the ventral base, and immediately after the segment which by means of a fleshy thread unites the abdomen with the thorax. Each pulmonary bursa is formed by the superposition of numerous, triangular, white, and extremely thin leaflets, which become confluent round the stigmata, and whose number exactly equals that of the pulmonary sacs. When there are four, a sort of fold or annular vestige found even in those where there are but two, and placed directly behind them, forms a line that separates the two pairs. The females have two very distinct ovaries, lodged in a spe- cies of capsule formed by the liver. In an unfecundated state they appear to be composed of a spongy, flaky kind of tissue, formed by the agglomeration of rounded, and scarcely visible corpuscles, which are the germs of eggs. As the results of PULMONARY. 167 fecundation become more apparent, the cluster formed by these ova(l) becomes less compact, and they are seen to be laterally inserted on several canals. Their great analogy to the ovaries of the Scorpions induces the same observer to pre- sume that they form meshes terminating in two distinct ovi- ducts, which open into a common vulva. The figure of the latter varies ; sometimes it is a longitudinal bilabiated slit, as in the Micrommata argetasia ; sometimes it is protected by an elongated operculum with a caudiform termination, as in the Epeira diadema; and at others resembles a tubercle. With respect to the simple eyes, or ocelli, he remarks, that they shine in darkness like those of Cats, and that the Araneides most probably enjoy the faculty both of nocturnal and diurnal vision. The abdomen becomes so putrid and decomposed after death, that its colours and even its form are soon destroyed. M. Dufour, by means of a rapid desiccation, the mode of which he points out, has succeeded in remedying this evil to a great degree. The silk, according to Reaumur, is first elaborated in two little reservoirs, shaped like tears of glass, placed obliquely, one on each side, at the base of six other reservoirs, resem- bling intestines, situated close to each other, flexed six or seven times, proceeding from a little beneath the origin of the abdomen, and terminating in the papillae by a very slen- der thread. It is in these ^ast mentioned vessels that the silk acquires a greater degree of firmness and other properties peculiar to it; they communicate with the preceding ones by branches, forming a number of geniculate turns, and then va- rious pieces of net-work(2). The newly spun filaments, when first drawn from the mammillae, are adhesive, and a certain degree of desiccation or evaporation is required to fit them for their destined purposes. When the temperature is propitious, (1) For their development and that of the foetus, see the admirable work of Herold. (2) See Treviranus, on the same subject. 168 ARACHNIDES. however, a single instant is sufficient, as the animal employs them the moment they escape from the apparatus. Those white and silky flocculi that may be observed floating about in spring and autumn in foggy weather, vulgarly termed in France fits de la Vicrge, are certainly produced as we have satisfactorily ascertained by tracing them to their point of origin by various young Araneides, those of the Epeirse and Thomisi particularly; they are mostly the larger threads which are intended to afford points of attachment to the radii of the web, or those that compose the chain, and which, becoming more ponderous by the access of moisture, sink, approach one another, and finally form little pellets: we frequently observe them collected near the web commenced by the Spider, and in which it resides. It is also very probable that many of these young animals not having as yet a sufficient supply of silk, limit their structure to throwing out simple threads. It is, I think, to the young Ly- cosse that we must attribute those which intersect the furrows of ploughed grounds, whose numbers are rendered so appa- rent by the reflection of light after sunrise. By chemical ana- lysis, these fils de la Vierge exhibit the same characters as the web of the spider: they are not then formed in the atmo- sphere, as, for want of proper observation, ex visu, that cele- brated naturalist, M. Lamarck, has conjectured. Gloves and stockings have been made with this silk ; but it was found im- possible to apply the process on a, large scale, and as it is sub- ject to many difficulties, is rather a matter of curiosity than utility. This substance, however, is of much greater impor- tance to the little animals in question. With it, the sedentary species, or those which do not roam abroad in search of their prey, weave webs(l) of a more or less compact tissue, whose form and position vary according to" the peculiar habits of each of them, and that are so many snares or traps, where the insects on which they feed become entangled, or are (1) Those of some exotic species are so strong 1 , that small birds arc entangled in them; they even oppose a certain degree of resistance to num. PULMONARI/E. 169 taken. No sooner is one of them arrested there by the hooks of its tarsi, than the Spider, some times placed in the centre of his net, or at the bottom of his web, or at others lying in ambush in a peculiar domicil situated near and in one of the angles, rushes towards his victim and endeavours to pierce him with his murderous dart, distilling into the wound a prompt and mortal poison ; should the former resist too vigor- ously, or should it be dangerous to the latter to approach it, he retreats, waiting until it has either exhausted its powers by struggling, or become more entangled in the net; but should there be no cause of fear, he hastens to bind it by in- volving the body in his silken threads, with which it is some- times completely enveloped. Lister says that Spiders dart their threads in the same way that the Porcupine darts his quills, with this difference, how- ever, that in the latter, according to the popular belief, the spines are detached from the body, whereas in the former, these threads, though propelled to a considerable distance, always remain connected with it. The possibility of this has been denied. Be it as it may, we have seen threads issuing from the mammillae of several Thomisi form straight lines, and when the animals moved circularly, producing movable radii. A second use to which this silk is applied by all female Ara- neides, is in the construction of the sacs destined to contain their eggs. The texture and form of these sacs are variously modified, according to the habits of the race. They are usually spheroidal ; some of them resemble a cap or tymbal, others are placed on a pedicle, and some are claviform. They are sometimes partially enveloped with foreign bodies, such as earth, leaves, &c. ; a finer material, or sort of tow or down, frequently surrounds the eggs in their interior, where they are free or agglutinated and more or less numerous. As they are voracious animals, the males, in order to avoid a surprise and to prevent themselves from falling victims to their pre- mature desires, approach their females in the nuptial season, with the greatest circumspection and mistrust. They cau- tiously and repeatedly touch them, and frequently for a long Vol. Ill W 170 ARACHNIDES. time before they yield to their wishes, and when this is the case they quickly and repeatedly apply the extremity of their palpi to the inferior surface of the abdomen, protruding at each time and as if by a spring, the fecundating organ con- tained in the button formed by the last joint of those palpi, and insinuate it into a sub -abdominal slit, near the base and between the respiratory orifices ; after a moment's interval the same act is repeatedly performed. Such is the mode of co- pulation of a small number of species belonging to the Orbi- telse. It is impossible to avoid feeling the most lively interest in reading what has been, written upon this subject by that learned naturalist, who of all others has most profoundly stu- died these animals, the celebrated Walckenaer, member of the Acad, des Inscriptions et Belles-lettres. The apparatus of the male organs of generation, or at least of what are consi- dered as such, is usually highly complicated and very various; it consists of scaly pieces, more or less hooked and irregular, and of a white fleshy body, on which sanguineous looking vessels are sometimes perceptible, which is considered as the fecundating organ, properly so called '; but in the Arachnides with four pulmonary sacs, and in some belonging to the divi- sion where there are but two, the last joint of the palpi of the males only exhibits a single horny piece in the form of a hook or ear- picker, without the smallest visible opening. Although Muller and others were mistaken when they placed the male organs of certain Entomostraca upon two of their antennae, it is very certain that the parts considered as analogous to them in the Araneides, are very different from those observed on the antennae of those Crustacea, and that if we refuse to admit of their exercising this function, it is impossible to con- ceive of their use(l). According to the experiments of Audebert, who has given us a history of the Monkeys worthy of the talents of that great painter, it is certain that a single fecundation is sufficient for several successive generations, but that with them, as with (l) They must at all events be organs of'.excitation. PULMONARY. " 171 all Insects and other analogous classes, the ova are sterile without a union of the sexes. Their nuptial season in France lasts from the latter end of summer till the beginning of Octo- ber. The ova first laid are frequently hatched before the ter- mination of autumn : the others remain in statu quo during the winter. The females of certain species of Lycosa have been observed to tear open the egg-sac when the young ones were about to issue from the ovum. The latter then mount on the back of their mother, where they remain some time. Other female Araneides carry their cocoons under the abdomen, or remain near them and watch them. The two posterior feet of some of the young ones are not developed until several days after they have been hatched. Some, during the same period, live together, and appear to spin in common. Their colour- ing is then more uniform, and the young naturalist may easily err in multiplying their species. One of our collabo- rators for the Encyclopedic Methodique, M. A. Lepelletier of Saint-Fargeau, has observed that these animals, as well as the Crustacea, possess the faculty of reproducing a lost limb. I have ascertained that a single wound from a moderate sized Araneid will kill our common Fly in a few minutes. It is also certain that the bite of those large Araneides of South America, which are there called Crab-Spiders, and are placed by us in the genus Mygale, kills the smaller vertebrated ani- mals, such as Humming-Birds, Pigeons, &c, and produces a violent fever in Man ; the sting of some species in the south of France has even occasionally proved fatal. We may therefore, without believing all the fabulous stories of Baglivi and others respecting the bite of the Tarantula, mistrust the Araneides, and particularly the larger ones. Various insects of the genus Sphex, Lin., seize upon these Spiders, pierce them with their sting, and transport them into holes where they have deposited their eggs, as a source of food for their young. Most of them perish in winter, but there are some which live several years such are the My- gales, the Lycosa, and probably several others. Although Pliny states that the genus Phalangium is unknown in Italy? 172 ARACHNIDES. we still presume that these latter Araneides and other large species which weave no web, as also the Galeodes and Solpu- gse, are the animals they collectively designated by that name, and of which they distinguished several species. Such also was the opinion of Mouffet, who, in his Theat. Insect., p. 219, has figured a Lycosa or Mygale, of the island of Can- dia, as a species of Phalangium. Lister was the first and most successful observer of the Spiders, whose habits he was enabled to study ; those of Great Britain laid the foundations of a natural arrangement, of which most of those that have been since published are mere modi- fications. The more pecent discovery of species peculiar to hot climates, such as the Jlraignee maponne described by the abbe Sauvages, and some others, the use of the organs of man- ducation introduced into the system by Fabricius, a more exact study of the general disposition of the eyes, and of their respective sizes, with that of the relative length of the legs, have all contributed to extend this classification. Walck- enaer has entered into the most minute of these details, and it would be a difficult matter to discover a species that could not find its place in some one of his divisions. One character, however, existed, the application of which had not been made general : I allude to the presence or absence of the third ter- minal hook of the tarsi. Savigny, so far as this is concerned, has given us a new method, of which, however, I have only seen a simple sketch(l). (1) See Walck., Faun. Franc, note to genus Mta. We knew nothing of the observations of M. Savigny on the Spiders, which ac- company the plates of Nat. Hist, of the great work on Egypt, until long after our article relative to the same animals was printed. That gentleman Hist. Nat. ut sup. establishes the following genera in the .family of the Araneides: 1. Ariadne, near that of Segestria, having but six eyes, of which the two intermediate posterior ones are further forwards; 2. Lachesis, near Drassus, but with the hooks of the Chelicerae, {forcipules, Savign.,) very small; 3. Ehigone, also allied to Drassus as well as to Clubiona; thorax very high before; second joint of the palpi spinous, and dilated into angle or tooth at the extremity; 4. Hersilia, allied to Agelena and Theridion of Walckenaer; feet long and slender, the superior nails bidentate; eyes united on an eminence, ar- ranged in two transverse lines, and curved backwards; two very long fusi PUEMONARI7E. 173 M. Leon Dufour, who has published many excellent me- moirs on the anatomy of Insects, who has especially studied those of Valencia, among which he has detected several new species, and to whose labours the science of Botany is not less indebted, has paid particular attention to the respiratory or- gans of spiders, and it is from him that we have taken our divisions, which consist of those that have four pulmonary sacs with as many external stigmata, two on each side, and closely approximated and of such as have but two(l). The first, which embraces the order of the Theraphosse of Walck- enaer, and some other genera of the one he collectively desig- nates by the name of Spiders, acccording to our method form but the single genus Mygale. Their eyes always situated at the anterior extremity of the thorax, and usually, closely approximated; feet and chelicerae robust; co- pulating organs of the males always salient and frequently very simple. Most of them have but four fusi, of which the two late- ral or external, situated somewhat above the others, are longest, and consist of three segments, exclusive of the prominence that forms their peduncle. They weave silken tubes in which they reside, and which they conceal either in holes excavated by them for that purpose, or under stones, bark of trees, or between leaves. The Theraphosse of Walckenaer will form a first division, the characters of which are: 1. Four(2) fusi, of which the two that are intermediate and inferior, are usually very short, and the two that are exterior, very salient; the hooks of the chelae doubled un- derneath, or along their carina or inferior edge, and not on the inner side of their internal face, or upon it; eight eyes always, usu- ally grouped on a little eminence, three on each side, forming a forming a tail; 5. Arachne, which does not appear to us to differ from Ange- lena; 6. Argyopes, Epeirs whose anterior, lateral eyes are much smaller than the others; 7- Enio, fifth family of the Theridion, Walck.; S. Ocyaee, second family of the Dolomedes, Id. ( 1 ) Section of the Territelae of our first edition. (2) 1 have perceived, in the Atypi, vestiges of two other mammillx, those which, in the Spiders of the ensuing division, are placed between the four exterior ones, and are, there, very visible; as they are here but scarcely apparent, I have not thought it requisite to notice them. 174 ARACHNIDES. reversed triangle, and the two superior ones approximated; the remaining two arranged transversely between the preceding. The fourth pair of legs are the longest, and then the first; the third is the shortest. Here the palpi are inserted into the superior extremity of the jaws; so that they appear to consist of six joints, the first of which, narrow and elongated, with the internal angle of the superior extre- mity salient, fulfils the functions of a jaw. The ligula is always small and nearly square. The last joint of the palpi of the males is short, has the form of a button, and bears the organs of genera- tion at its extremity. The two anterior legs of the same sex have a stout spine or spur at their inferior extremity. Such are the cha- racters of the Mygale, Walck., Or the true Mygales. In some of them we fin:l no transverse series of horny and movable spines or points, resembling the teeth of a rake, at the superior extremity of their chelicerae immediately above the insertion of the claw or hook which terminates them. The hairs which decorate the under part of their tarsi, form a thick and broad brush, projecting beyond the hooks, and usually conceal- ing them. The male organs of generation consist of a single scaly piece, terminated by an entire point, or neither emarginated nor divided; sometimes it is formed like an ear-pick M. de la Blond, Lat. usually, however, it is globular inferiorly, then becomes nar- row, terminates in a point, and forms a kind of arcuated hook. This division is composed of the largest species of the family, some of which, when at rest, cover a circular space of from six to seven inches in diameter; they sometimes seize upon Humming- birds. They establish their domicil in the clefts of trees, under the bark, in the fissures of rocks, or on the surface of leaves of various plants. The cell of the Mygale avicularia has the form of a tube, narrowed into a point at its posterior extremity. It consists of a white web, of a close, very fine texture, semi-diaphanous, and resem- bling muslin. One of them, presented to me by M. Goudot, when unrolled, was about two decimetres in length, and six centimetres in breadth, measured across its greatest transversal diameter. The cocoon of the same species was of the figure and size of a large walnut. Its envelope, consisting of the same material as that of its domicil, was formed of three layers. It appears that the young are hatched in it, and undergo their first change of tegument there. PULMONARIJE. 175 The naturalist just mentioned, stated to me, that he had taken a hundred of them from a single cocoon(l). This Mygale Aranea avicularia, L.; Kleem. Insect. XI, and XII, the male is about an inch and a half long, blackish, and extremely hairy; the extremity of the feet and palpi, and the inferior pili of the mouth reddish. The genital organ of the male is hollow at base, and terminates in an elongated and very acute point. South America and the Antilles produce other species, called by the French colonists Jlraignees-crabes. Their bite is reputed to be dangerous. A very large species M.fasciata; Seb., Mus., I, lxix, i; Walck., Hist, of Spiders, IV, i, the female is also found in the East Indies. A species, nearly as large as the avicularia, inhabits the Cape of Good Hope. Another of the same division M. Valentino, was discovered in the sandy and desert districts of Moxenta, in Spain, by M. Dufour, who has described and figured it in the Ann. of the Phys. Sciences, Brussels, vol. V. Walckenaer has also described a second species from that peninsula which has two prominences above its respiratory organs. These two latter species form a parti- cular group, characterized by the hooks of the tarsi, which are salient or exposed(2). In the following Mygales(3), the superior extremity of the first joint of the-chelicerae presents a series of spines, articulated and movable at base according to the observations of Dufour and forming a sort of rake. The tarsi are Jess pilose underneath than in the preceding divi- sion, and their hooks are always exposed. The males of one species, the only ones I have seen, have more complicated organs of gene- ration than those of the preceding division. The principal and scaly piece incloses a peculiar, semiglobular body, terminating in a bifid point, in an inferior cavity(4). These species, in the dry and mountain districts of the south of Europe and of some other countries, excavate subterraneous galle- (1) See my memoir on the habits of -the Avicularia in the Ann. du Mus. d'Hist. Nat. VIII, p. 456. (2) For details concerning these and the following species, as well as for the other genera of this family, see the corresponding articles in the Nouv. Diet. d'Hist. Nat., where we treat of them at length. (3) The genus Cteniza, Lat., Fam. Nat. du Regno Animal. (4) On this point I am contradicted by M, Dufour. I was compelled again to examine the fact, and have convinced myself that I was not mistaken. It is poss- ible the specimens he examined did not present this character. 176 ARACHNIDES. ries, which are frequently two feet in depth, and so extremely tortu- ous, that, according to Dufour, it is frequently impossible to trace them. At the mouth, they construct a movable operculum with earth and silk, fixed by a hinge, which, from its form, nicely adjusted to the aperture, its inclination, its weight, and the superior position of the hinge, spontaneously shuts, and completely closes the entrance of their habitation, forming a kind of trap-door, which is scarcely distinguishable from the surrounding earth. Its inner surface is lined with a layer of silk, to which the animal clings, in order to keep its door shut and prevent intruders from opening it. If it be slightly raised, it is a sure indication that the owner is within. Unearthed by laying open the gallery front of the entrance, it be- comes stupified, and allows itself to be captured without resistance. A silken tube, or the nest properly so called, lines the inside of the gallery. M. Dufour thinks that the males never excavate. Inde- pendently of his having found them under stones only, they do not seem to him so well prepared with organs adapted to such work(l). Without deciding upon this point, we presume, with him, that the Mygale carminans of France Nouv. Diet. d'Hist. Nat., art. Mv- gale is merely the male of the following species: Walckenaer, however, doubts it. M. csementaria, Lat.; Jlraignee maconne, Sauvag., Hist, de l'Acad. des Sc, 1758, p. 26; Araignee mineuse, Dorthes., Trans. Lin. Soc. II, 17, 8; Walck., Hist, des Aran., fasc. Ill, x; Faun. Franc., Arach., II, 4; Dufour, Ann. des Sc. Phys., V, lxxiii, 5. The female Mason Spider, as it is called, is about eight lines in length, of a reddish colour, verging on a brown more or less deep; edges of the thorax paler. The chelicerae are blackish, each one furnished above, near the articulation of the hook, with five points, of which the internal is the shortest. The abdomen is of a mouse-grey, with streaks of a darker hue. The first joint of all the tarsi is furnished with small spines. The hooks of the last have a spur at their base, and a double range of acute teeth. The mammillae are but slightly prominent. According to Dufour Ann. des Sc. Phys., V, lxxiii, 4 the supposed male, of which I have made a species, M. cardeiise, differs from the preceding individual in the greater length of its feet, in the hooks of the tarsi, which are twice the number of the other, but have no spurs, and in the diminished length of its mammillae. A more apparent character may be found in the (1) See his excellent memoir entitled," Observations sur quelques Arachnides Quadripulmonaires. " PULM0NARI7E. 177 stout spine, which terminates, inferiorly, the two anterior tibiae. This Mygale is found in the southern departments of France situated on the borders of the Mediterranean, in Spain, &c. M.fodiens, Walck., Faun. Franc., Arach., II, 1, 2; M. Sau- vagesii, Dufour, Ann. des Sc. Phys., V, lxxiii, 3; Jlranea Sau- vagesii, Ross. The female is somewhat larger than that of the preceding species, and of a light reddish-brown, without spots. The exterior fusi are long. The four anterior tarsi are alone furnished with small spines; all have a spur at the end, and their hooks have but a single tooth, situated at their base. The chelicerae are stouter and more bent than those of the Csementaria; the teeth of the rake are rather more numerous, and there are two ranges of teeth under the first joint. The male is unknown. This species is found in Tuscany and Cor- sica. There is a small clod of earth in the Museum d'Hist. Nat. of Paris, in which are four of its nests, forming a regular quadrilateral figure. M. Lefevre, who has made so many sacrifices to the science of Entomology, has discovered a new species of Mygale in Sicily, the entire body of which is of a blackish brown. The extremity of the anterior tibiae of the male does not exhibit that stout spine which appears to be peculiar to individuals of the same sex, in the other Mygales. Another species is found in Jamaica M. nidulans figured, together with its nest, by Brown in his Nat. Hist, of Jamaica, pi. xliv, 3. There, the palpi are inserted into an inferior dilatation of the ex- ternal side of the jaws, and consist of but five joints. The ligula, at first very small Atypus lengthens, and then advances between the jaws, and this character becomes general. The last joint of the palpi, in both sexes, is elongated, and pointed near the end. There is no spur to the extremity of the anterior tibiae of the males. ATYrus, Lat. Oletera, Walck. The Atypi have a very small ligula almost covered by the internal portion of the base of the jaws, and closely approximated eyes grouped on a tubercle. Jitypus Sulzeri, Lat., Gener. Crust, et Insect., I, v, 2, the male; Dufour, Ann. des Sc. Phys., V, lxxiii, 6; Jlranea picea, Sulz.; Oletere atype, Walck., Faun. Frang., Arach., II, 3. Body entirely blackish, and about eight lines in length. The thorax is nearly square, depressed posteriorly, inflated, widened, and broadly truncated anteriorly, presenting an appearance very Vol. III. X 178 ARACHN1DES. different from that of the same part in the Mygales. The che- licerae are very stout, and underneath the claw and at its base is a little eminence resembling a tooth. The last joint of the palpi of the male is pointed at the end. From the genital organ arises, inferiorly, a little squamous semi-diaphanous piece, widened and unequally bidentated at the end, with a small seta or cirrus at one of its extremities. This species excavates a cylindrical gallery in sloping grounds covered with grass; in this gallery, seven or eight inches in length, horizontal at first and then inclined, it weaves a tube of white silk of the same form and dimensions. The cocoon is fastened with silk by both ends to the bottom of the gallery. It is found in the environs of Paris and Bourdeaux; M. Basoches has observed a variety near Seez, which is always of a light brown. M. Milbert has discovered another species Mypus rufipes near Philadelphia, which is entirely black, with fulvous feet. Eriodon, Lat. Missulena, Walck. The Eriodons differ from the Atypi in their elongated, narrow ligula advancing between their jaws, and in their eyes, which are scattered over the anterior part of the thorax. The only species known Eriodon occatorius, Lat.; Missulena occatoria, Walck., Tabl. des Aran. pi. II, ii, 12 is an inch long, blackish, and peculiar to New Holland, where it was discovered by MM. Peron and Lesueur(l). In our second and last division of the quadripulmonary Spiders or Mygales, we find characters common to Eriodon, such as the ligula being prolonged between the jaws, and the palpi consisting of five joints; but the claws of the chelicerae are folded over their inner face, there are six fusi, their first pair of legs is the longest and not the fourth, and the third is always the shortest. Some of them have but six eyes. The number of pulmonary sacs will not allow us to remove the subgenera of this division from the preceding ones, and as they conduct us toDrassus, Clotho, and Segestria, sub- genera with but two pulmonary sacs, the natural order will not per- (1) In the first memoir of M. Dalman upon the Insects found in amber, that celebrated naturalist mentions (p. 25) a Spider which, it appeared to him, should be made the type of a new genus (Chalinura). The eyes are placed on a very high anterior tubercle, four of them, of which the two anterior are very large and ap- proximated, occupying the centre. The external fusi are much elongated. From these characters it would seem that this spider approaches Mygale or some other analogous genus. PULMONARIiE. 179 mit us to pass from the Mygales to the Lycosae and other hunting or wandering Spiders. The Mygales are true tapissieres or true spiders which line their galleries with silk and in fact, it was in this division that the Aranea avicularia of Linnaeus was formerly placed. This second division comprises the two following subgenera. Dysdera, Lat. But six eyes arranged in the figure of a horse-shoe, the opening in front; the chelicerae very stout and projecting; jaws straight and dilated at the insertion of the palpi(l). Filistata, Lat. Eight eyes grouped on a little eminence at the anterior extremity of the thorax; the chelicerae small; the jaws arcuated on the outer side, and surrounding the ligula(2). We now pass to Araneides with but one pair of pulmonary sacs, and as many stigmata. They all have palpi formed of five joints, inserted into the external side of the jaws near their base, and most frequently in a sinus; a ligula extending between them, either nearly square, triangular or semicircular, and six fusi at the anus. The last joint of the palpi, in the males, is more or less ovoid, and usually encloses, in an excavation, a complicated and varied organ of copu- lation; it is rarely Segestria exposed. With the exception of a few species, which enter into the genus Mygale, they compose that of Aranea, Lin. Araneus of some authors. A first division will comprehe'nd the Aranea Sedentari^e, or seden- tary spiders. They make webs, or throw out threads to ensnare their prey, and always remain in these traps, or their vicinity, as well as near their eggs. Their eyes are approximated anteriorly and are sometimes eight in number, of which four or two are in the middle and two or three on each side, and sometimes six. Some, which, from the circumstance of their always moving for- wards, we term the Rectigrad^, weave webs and are stationary; (1) Dysdera erythrina, Lat.; Walck., Tab. des Aran., V, 49, 50; Dufour, Ann. des Sc. Phys. V, lxxiii, 7; Aranea rufipes, Fab.; Dysdera parvula, Dufour, lb. (2) Filistata bicolor, Lat.; Walck., Faun. Franc, Arach., VI, 1 3. A moderate sized species is found at Guadaloupe, the male of which has long and slender legs, curved palpi, with the genital organs situated at the extremity of the last joint, and terminated by a slender and arcuated, or falciform hook. 180 ARACHN1DES. their legs are elevated when at rest; sometimes the two first and two last are the longest, and at others those of the two anterior pairs, or the fourth and the third. The general arrangement of the eyes does not form the segment of a circle or a crescent. They may be divided into three sections: the first, or that of the Tubitelas, has cylindrical fusi approximated into a fasciculus di- rected backwards; the legs are robust, the two first or the two last, and vice versa, longest in some, and the whole eight nearly equal in others. We will commence with two subgenera, which, with respect to the jaws that describe a circle round the ligula, approach the Filistatae, and are removed from those that follow. Clotho, Walck. Uroctea, Dufour. A singular subgenus. The chelicerae are very small, can sepa- rate but little thereby approximating this subgenus to the last and are not indented; very small hooks; the shortness of the body and length of the legs produce a resemblance to the Crab-Spiders or Thomisi. The relative length of these organs differs but little; the fourth pair, and then the preceding one are merely somewhat longer than the first; the tarsi, only, are furnished with spines. The eyes are further from the anterior margin of the thorax than in the fol- lowing subgenus, and are approximated and arranged as in the genus Mygale of Walckenaer; three on each side form a reversed triangle; the two others form a transverse line in the space comprised between the two triangles. The jaws and the ligula are proportiona- bly smaller than those of the same subgenus; a short projection or slight dilatation on the external side of the jaws, gives insertion to the palpi; the jaws terminate in a pebnt; the ligula is triangular and not nearly oval as in Drassus. The two superior or most lateral fusi are long, but what, according to Dufour, particularly charac- terizes his Urocteae or our Clothos, is, that there are two pecti- niform valves which open and shut at the will of the animal(l), in place of the two intermediate fusi. But a single species is known, the Uroctea 5-maculata^ Du- four, Ann. des Sc. Phys., V, lxxvi, 1; Clotho Durandii, Lat. (1) I have seen, in a well preserved specimen, six fusi, of which the two superior were much the longest and terminated by an elongated joint, forming an elliptical lamina, and the other four small, the inferior ones particularly, and ar- ranged in a square. The anus, placed under a little membranous projection resembling a clypeus, was furnished on each side with a pencil of retractile hairs. These pencils are the parts named by Dufour pectiniform valves, and are distinct from the two intermediate fusi, which are concealed by the two inferior ones. PULMONARI^E. 181 The body is five lines in length, of a fine chesnut colour; abdo- men black; five small, round, yellowish spots above, four of which are arranged transversely in pairs, and the last or fifth posterior; legs hairy. It is evident from the plates of the great work on Egypt, that M. Savigny found it in that country, and proposed forming anew genus with it. Count Dejean brought it from Dalmatia; and Schreiber, director of the Imperial Mu- seum of Vienna, has sent me specimens captured in the same country. M. Dufour also found it in the mountains of Nar- bonne, in the Pyrennees and among the rocks of Catalonia. To this latter naturalist we are indebted not only for our know- ledge of the external characters of this spider, but for many curious observations relative to its habits. " She constructs," says he, " a shell resembling a calotte or patella an inch in diameter, on the under surface of large stones or in the fissures of rocks. Its contour presents seven or eight emarginations, the angles of which are alone attached to the stone by silken fasciculi, the margin being free. This singular tent is admira- bly woven. The exterior resembles the very finest taffeta, formed, according to the age of the animal, of a greater or less number of layers. Thus, when the young Uroctea first com- mences her establishment, she merely forms two webs between which she seeks for shelter. Subsequently, and I believe at each change of tegument, she adds a certain number of layers. Finally, when the nuptial season has arrived, she lines an apart- ment with a softer and more downy material which is to en- close the sac of eggs and young ones. Although the exterior shell is more or less soiled by foreign bodies which serve to conceal it, the chamber of the industrious architect is always extremely neat and clean. There are four, five, or six egg- pouches or sacculi in each domicil; they are lenticular, more than four lines in diameter, and formed of a snow-white taffeta lined with the softest down. The ova are not produced till the latter end of December or the beginning of January; the young are to be protected from the rigour of winter and the incursions of enemies -all is prepared; the receptacle of this precious de- posit is separated from the web that adheres to the stone by soft down, and from the external calotte by the various layers I have mentioned. Some of the emarginations in the edge of the pavilion are completely closed by the continuity of the web, the edges of the remainder are merely laid on each other, so that by raising them up, the animal can issue from its tent or enter it, at pleasure. When the Uroctea leaves her habitation for the chase, she has nothing to fear, she only possesses the 182 ARACHNIDES. secret of the impenetrable emargination, and has the key to those which alone afford an entrance. When her offspring are able to provide for themselves, they leave their native dwelling, to establish elsewhere their individual habitations, while the mother returns to it and dies it is thus her cradle and her tomb." Drassus, Walck. The Drassi differ from Clotho in several characters. Their che- licerae are robust, projecting and dentated beneath; their jaws are ob- liquely truncated at the extremity, and the ligula forms an inferiorly truncated oval, or an elongated curvilinear triangle; the eyes are nearer to the anterior margin of the thorax, and the line formed by the four posterior ones is longer than the anterior, or extends beyond it on the sides. There is but little difference in the proportions of the fusi, and we do not observe between them the two pectini- form valves peculiar to Clotho. Finally, the fourth pair of legs, and then the first, are manifestly longer than the others. The tibiae and first joint of the tarsi are armed with spines. These Spiders live under stones, in the fissures of walls, and on leaves; they construct their cells with an extremely white silk. The cocoons of some are orbicular and flattened, and consist of two valves laid one on the other. M. Walckenaer distributes the Drassi into three families, according to the direction and approximation of the lines formed by the eyes, and the greater or less dilatation of the middle of the jaws. The species which he calls viridissimus, Hist, des Aran, fascic. IV, 9, and which alone composes his third division, weaves a fine, white, transparent web on the surface of a leaf; under this web it seeks for shelter. I have sometimes observed a similar web on the leaf of the Pear-tree, but the margin was angular and resembling a tent, like that of the Clotho, beneath which was the cocoon. It is, I presume, the work of this species of Drassus, and proves the analogy of this subgenus with the pre- ceding one. M. Leon Dufour, Ann. des Sc. Phys., VI, xcv, 1, has given a very complete description of a species of Dras- sus D. segestriformis found by him under stones in the highest Pyrennees,and never beneath the Alpine region. It is one of the largest of this subgenus, and appears to me to be closely allied to my melctnogaster, which I believe to be the D. lucifugus of Walckenaer, Schaeff. Icon. CI, 7. One of the prettiest species, which is very commonly observed running along the ground in the vicinity of Paris, is the D. relucens. It is small, and almost cylindrical, with a fulvous PULMONARY. 183 thorax, invested with a purple silky down; the abdomen is a mixture of blue, red, and green, with metallic reflections, and marked by two transverse and golden lines, of which the ante- rior is arcuated. Four golden dots are sometimes observed on it(l). In the other Tubitelae the jaws do not surround the ligula; their external side is dilated inferiorly beneath the origin of the palpi. Some have but six eyes, four of which are anterior, and form a transverse line, and the two others posterior, situated, one on each side, behind the two lateral ones of the preceding line. Such is the essential character of the Segestria, Lat. The ligula is elongated and almost square. The first pair of legs, and then the second, is the longest; the third is the shortest. These spiders construct long, silky, cylindrical tubes in the chinks and crevices of old walls, which they inhabit; their first pairs of legs are always directed forwards, and diverging threads border the external entrance of their domicil, forming a net for ensnaring Insects. The genital organ of the S. perfida Aranea Jlorentina, Ross., Faun. Etrusc, XIX, 3 a large black species with green chelicerse, which is not rare in France, is shaped like a tear, or is ovoido-conical, very acute at the end, entirely salient, and red(2). The remaining Tubitelae have eight eyes. On account of the dif- ference in the site of their habitations, we may divide them into the terrestrial and the aquatic. Although the last family of the Ara- neides of Walckenaer (his Naiades) is composed of these latter, they are so closely allied to the other Tubitelae, that notwithstanding this disparity of habits they must be placed together. In those which are terrestrial, the ligula is almost square, or but very slightly narrowed, with a very obtuse or truncated summit; the jaws are straight, or nearly so, and more or less dilated towards the extremity; the two eyes of each lateral extremity of the ocular group are generally separated from each other, or at least are geminate and placed on a particular eminence like those of the aquatic Tubitelae. Clubiona, Lat. This subgenus is only distinguished from the following one by (1) For the other species, see Faun. Paris., Walck., andTabl. des Aran., Id. (2) Add the Seg. senocnhta, Walck., Hist, des Aran., V, vii; Aranea smoculata, L.;Deg. 184 ARACHNIDES. the nearly equal length of the exterior fusi, and by the straight- ness of the line formed by the four anterior eyes. The Clubionse construct silky tubes under stones, in chinks of walls, or between leaves. Their cocoons are globular(l). Aranea. The true Araneae, which we at first designated by the generic ap- pellation of Tegenaria, retained by Walckenaer, and to which we add his Angelense and Nyssi, have their two superior fusi much longer than the others, and their four anterior eyes arranged in a line posteriorly arcuated or forming a curve. They construct, in our houses, in the angles of walls, on plants, hedges, along the roads, in the earth, and under stones, a large and nearly horizontal web, at the upper part of which is a tube where they remain motionless(2). Then follow the Naiades of Walckenaer, or our aquatic Tubitelae, which form the Argyroneta, Lat. The jaws are inclined on the ligula, which is triangular. The two eyes of each lateral extremity of the ocular group are closely approximated and placed on a particular eminence; the four others form a quadrilateral. Argyroneta aquatica; Aranea aquatica, L., Geoff., Deg. Blackish brown, the abdomen darker; silky; four depressed points on the back. It is found on the stagnant waters of Eu- rope, where it swims with the abdomen enclosed in a bubble of air; it forms an oval cell, filled with air, and lined with silk, from which various threads extend to the surrounding plants. Here it lies in wait for its prey, deposits its cocoon, which it carefully watches, and encloses itself to pass the winter. In the second section of the sedentary and rectigrade spiders, that of the iNEQuiTELiE, the external papillae are nearly conical, project but little, are convergent, and form a rosette; the legs are very slen- der. The jaws incline over the lip, and become narrower at their superior extremity, or at least do not sensibly widen. Most of them have the first pair of legs longest, and then the (1) Aranea holosericea, L. ; Degeer, Fab. ; Walck., Hist, des Aran. IV, iii, fern. ; Aranea atrosc. Beg., Fab.; List., Aran., XXI, 21; Albin, Aran., X, 48, and XVII, 82. See also Tab. des Aran., and the Faun. Paris., Walckenaer. (2) Aranea domcstica, L., Deg., Fab.; Clerck., Aran. Suec, pi. ii, tab. ix; Tegencria civilis, Walck., Hist, des Aran., V, v; iranea lubyrinthica, L.,Fab.: Clerck, Aran., Suec pi. ii, tab. viii. See the Tab. des Aran., Walck. pulmonarite. 185 fourth. The abdomen is more voluminous, softer, and more colour- ed than in the preceding tribes. Their webs form an irregular net composed of threads which cross each other in every direction and on several planes. They lie in wait for their prey, display much anxiety for the preservation of their eggs, and never abandon them till they are hatched. They are short-lived. In some, the first pair of legs, and then the fourth, are the longest. Scytodes, Lat. But six eyes arranged in pairs. According to Dufour, the hooks of their tarsi are inserted into a supplementary joint. Two species are known, one of which, the thoracica( 1) in- habits houses in Europe, and the other, la blonde, Ann. des Sc. Phys. V, Ixxvi, 5, was found under calcareous debris in the mountains of Valencia. It weaves a uniform tube of a thin milk-while tissue, like that of the Dysdera erythrina. Theridion, Walck. Eight eyes disposed as follows: four in the middle forming a square, the two anterior of which are placed on a little eminence, and two on each side, also situated on a common elevation. The thorax has the figure of a reversed heart, or is nearly triangular. This subgenus is very numerous(2). Therid< malmignatte; JLranea 13-gultata, Fab.; Ross. Faun. Etrusc, II, ix, 10. The lateral eyes separated from each other; body black, with thirteen small, round, blood-red spots on the abdomen. Its bite is considered venomous and even mortal. From Tuscany and Corsica(S). The A. madam. Fab., a second species of Theridion inhabit- ing South America, is equally dreaded in that country. This prejudice against these animals appears to originate from their black colour, varied with sanguine spots. (1) Scytodes thoracica, Lat., Gen. Crust, et Insect. I, v, 4; Walck. Hist, des Aran., I, x, and II, Suppl. (2) See the Tab. and Hist, des Aran., Walcken., the Ann. des Sc. Nat., and Ann. des Sc. Phys. The Aranese bipundata, redimita, L., and the A. albo-maculata, Deg\, &c, should be referred to this genus. (3) This species is the type of the genus Latrodeda, Walck., which he distin- guishes from that of Theridion by the difference in the respective length of the feet; in this, however, he appears to me to have erred. His Theridion benignum, Hist, des Aran. fasc. V, viii, whose habits he has care- fully studied, establishes its domicil between the clusters of grapes, and defends them from the attacks of various Insects. Vol. Ill Y 186 ARACHNIDES. Episinus, Walck. Eight eyes also, but they are approximated on a common eleva- tion; the thorax is narrow and almost cylindrical l). In the remaining Inequitelae, the first pair of legs, and then the second, are the longest. Such is the Pholcus, Walck. Where the eight eyes are placed on a tubercle, and divided into three groups; one on each side consisting of three eyes, forming a triangle, and the third in the middle, somewhat anteriorly, and com- posed of two on a transverse line. Ph. phalangioides, Walck., Hist, des Aran., fasc. V, tab. x; draignee domestique a longues pattes, Geoff. The body long, narrow, pale yellowish or livid, and pubescent; abdomen nearly cylindrical, very soft, and marked above with blackish spots; very long, slender legs; a whitish ring round the extremity of the thighs and tibiae. Common in houses, where it spins a web of a loose texture, in the angles of the walls. The female cements her eggs into a round naked mass, which she carries between her mandibles. M. Dufour has found a second species, the Pholque a queue Ann. des Sc. Phys. V, lxxvi, 2, in the clefts of the rocks in Moxente, Valencia. Its abdomen terminates in a conical point, and thus forms a sort of tail, like that of the Epeira conica. Like the preceding species, it balances its body and feet. The genital organs of the male are very complex. In the third section of the sedentary rectigrade spiders, the Or- bit:el;, or Jiraignees Tendeuses of others, the external fusi are almost conical, slightly salient, convergent, and form a rosette; the legs are slender, as in the preceding section, but the jaws are straight and evidently wider at their extremity. The first pair of legs, and then the second, are always the longest. There are eight eyes thus arranged: four in the middle forming a quadrilateral, and two on each side. The Orbitelae approach the Inequitelae in the size, softness, and diversity of colour of the abdomen, and in their short term of exist- ence; but their web is a regular piece of net-work, composed of con- centric circles intercepted by straight radii diverging from the cen- tre, where they almost always remain, and in an inverted position, at the circumference. Some conceal themselves in a cell or cavity (1) Episinus truncatus, Lat. Gener. Crust, et Insect, t. IV, p. 371. Italy, and environs of Paris. PULM0NARI2E. 187 which they have constructed near the margin of the web, which is sometimes horizontal, and at others perpendicular. Their eggs are agglutinated, very numerous, and inclosed in a voluminous cocoon. The threads which support the web, and which can be extended one-fifth of their length, are used for the divisions of the microme- ter. This observation was communicated to us by M. Arrago. Linyphia, Lat. The Linyphiae are well characterized by the disposition of their eyes: four in the middle form a trapezium, the posterior side of which is widest, and is occupied by two eyes much larger and more distant; the remaining four are grouped in pairs, one on each side, and in an oblique line. The jaws are only widened at their superior extremity. They construct on bushes a loose, thin, horizontal web, attaching to its upper surface, at different points, or irregularly, separate threads. The animal remains at its inferior portion, and in a re- versed position(l). Uloborus, Lat. The four posterior eyes placed at equal intervals on a straight line, and the two lateral ones of the first line nearer to the anterior edge of the thorax than the two comprised between them, so that this line is arcuated posteriorly. Their jaws, like those of the Epei- rse, begin to widen a little above their base, and terminate in the form of a palette or spatula. The tarsi of the three last pairs of legs terminate by one small nail. The first joint of the two posterior ones has a range of small seta?. The body of these animals, as well as in the following subgenus, is elongated and nearly cylindrical. Placed in the centre of their web, they advance their four anterior legs in a straight line, and extend the two last in an opposite direction; those of the third pair project laterally. These Arachnides construct webs similar to those of other Orbi- telse, but they are looser and more horizontal. They will completely envelope the body of a small coleopterous insect in less than three minutes. Their cocoon is narrow, elongated, angular at the margin, and suspended vertically to a web by one of its extremities. The other end is bifurcated or terminated by two prolonged angles one of which is shorter than the other and obtuse; there are two (1) Linyphia triangularis, Walck., Hist. desAran., V, ix, female; Aranearesu- pina sylvestris, De Geer; Aranea memtana, L.; Clerck., Aran. Suec, pi. Ill, Tab. I; Aranea resupinu domestica, De Geer. 188 ARACHNIDES. acute angles on each side. For these interesting observations I am indebted to my friend M. Leon Dufour. Uloborus Walckenaerius, Lat.(l) About five lines in length; reddish-yellowish; covered with a silky down forming two series of little fasciculi on the top of the abdomen; paler rings on the legs. From the woods in the vicinity of Bourdeaux, and in va- rious departments of the south of France. Tetragnatha, Lat. The eyes placed four by four on two nearly parallel lines, and separated by almost equal intervals; jaws long, narrow, and only widened at their superior extremity. The chelicers are also very long, in the males especially. The web is vertical(2). Epeira, Walck. The two eyes on each side approximated by pairs, and almost con- tiguous; the remaining four forming a quadrilateral in the middle* The jaws dilate from their base, and form a rounded palette. The ciicurbit'ma is the only species known whose web is horizon- tal; that of the others is vertical, or sometimes oblique. Some place themselves in its centre in a reversed position, or with their head downwards; others construct a domicil close by it, either vaulted on all sides, or forming a silky tube composed of leaves drawn together by threads, or open above, and resembling a cup or the nest of a bird. The web of some exotic species is formed of such stout materials that it will arrest small Birds, and even impede the progress of a Man. Their cocoon is usually globular; that of some species, however, is a truncated oval, or very short cone. The natives of New Holland Voyage a la recherche de la Pey- rouse, p. 239 and those of some of the South Sea Islands, for want of other food, eat a species of Epeira, closely allied to the Jiranea esuriens, Fab. M. Walckenaer, in his Tableau des Araneides, mentions sixty-four species of Epeirae, remarkable, in general, for the diversity of their colours, form and habits. He has arranged them in various small and very natural families, the study of which we have endeavoured to simplify in the second edition of the Nouv. Diet. d'Hist. Nat., article Epe'ire. Certain important considerations, such as those of (1) Lat, Gen. Crust, et Insect., I, 109; see also second edition of the Nouv. Diet. d'Hist. Nat., article Ulobore. (2) Tetragnatha extensa, Walck., Hist, des Aran., V, vi; Aranea externa, L., Fab. , De Geer; Aranea virescens? Fab.; Aranea maxillosa, Id. See Tab. des Aran, of Walckenaer. PULMONARY. 189 the sexual organs, had been neglected or were not sufficiently attended to; thus, for instance, the female Ep. diadema, and others, present at the part which characterizes their sex, a singular appendage, which reminds us of the apron of the Hottentot women. These species should constitute a separate division. By pursuing this ex- amination, other not less natural divisions might be established. We will content ourselves with mentioning a few of the principal species, commencing with those that are indigenous to Europe. Ep. diadema; Jlranea diadema, L., Fab.; Roes., Insect. IV, xxxv xl. Large, reddish, velvety; abdomen of the females extremely voluminous, particularly when about to lay their eggs, and of a deep brown or yellowish red; a large rounded tubercle each side of the back near its base, and a triple cross, formed of small white spots or dots; palpi and legs spotted with black. Very common in Europe in autumn. The eggs are hatched in the spring of the ensuing year. Ep. scalaris; Jlranea scalaris, Fab.; Panz., Faun. IV, xxiv. Thorax reddish; top of the abdomen usually white, with a black spot in the form of a reversed triangle, oblong and dentated. weaves its web along the banks of ponds, brooks, Sec. Ep. cicatricosa; Jlranea cieatricosa, De Geer; Jl. impressa, Fab. The abdomen flattened, and of a greyish brown or obscure yel- lowish; a black band, festooned and edged with grey along the middle of the back; eight or ten large impressed points in two lines. It constructs its web on walls or other bodies, and re- mains concealed in a nest of white silk, which it forms under some projecting object, or in some cavity in the vicinity. It only works and feeds during the night, or when the light of day is but weak. It retires under the bark of old trees or logs. Ep. sericea, Walck., op. cit., Ill, ii. Covered above with a silvery and silken down; abdomen flattened, immaculate and with festooned margins. South of Europe and Senegal. Ep. fusca, Walck., Hist, des Aran. II, i, the female. Very common in the cellars of Angers. Its cocoon is white, almost globular, fixed by a pedicle, and composed of very fine threads; it is soft to the touch, like wool. That of the Ep. fasciata, Walck., op. cit. Ill, i, the female, is about an inch long; it resembles a little balloon, of a grey colour, with longitudinal black stripes, one of whose extremities is truncated and closed by a flat and silky operculum; a fine down envelopes the eggs in its interior. This species weaves a vertical and irregular web, in the middle of which it remains, along the banks of rivulets, 8cc. Its thorax is covered with a soft and silvery down, and its abdomen is of a beautiful yellow, inter- sected at intervals with transverse brown, or blackish-brown 190 ARACHNIDES. lines, arcuated and slightly undulated. M. Leon Dufour, Ann. des Sc. Phys. VI, pl.xcv, 5, has given a detailed description of this species, and of its habits, and was the first who ascertained the male. He has figured its sexual organ. The penis resem- bles a twisted seta. Ep. cucurbitina; Jtranea cucurbitina, L.; Ji. senoculata, Fab.; Walck. Hist, des Aran., Ill, iii. Small; abdomen ovoid and lemon-coloured, marked with black points; a red spot on the anus. It weaves a small horizontal web between the stems and leaves of plants. Ep. conica; Jlranea conica, De Geer and Pall.; Walck. Hist. Nat. des Aran., Ill, iii. Remarkable for its abdomen, which is gibbous anteriorly and has a conical termination; the anus is placed in the centre of an eminence. When it has extracted the juices from an insect, it suspends it to a thread. Immediately after the conica, We may place the species called by Dufour Epe'ire de Vopuntia Ann. des Sc. Phys., V, lxix, 3 - from the circumstance of its always weaving its loose and irregular web among the leaves of the Agave and Opuntia. It is black, with white hairs laid close to the body, having an appearance of scales. The abdomen has two pyramidal tuber- cles on each side, and terminates posteriorly in two others, which are obtuse and separated by a wide emargination. The posterior face of each tubercle is marked with a beautiful snow- white spot, resembling nacre; these spots are connected with each other, and with one or two more behind them, by white zig-zag lines. In the newly-hatched animal, these tubercles are not visible. The cocoons are oval, whitish, and formed of two coats, the interior of which is a kind of tow that envelopes the ova. Seven, eight, and even ten of these cocoons are frequently found arranged in file, or one after another. From Catalonia and Valencia. Some of the species foreign to Europe are very remarkable. Here we observe the abdomen is invested with an extremely firm skin, furnished with points or horny spines(l); and there the legs are provided with bundles of hairs(2). (1) The Jlr. militaris, spinosu, cancriformis, hexacaniha, tctracantha, geminata, fornicata, of Fabricius. M. Vauthier, one of our best painters of subjects of na- tural history, has described and figured, Ann. des Sc. Nat., I, p. 161, a species of this division curvicauda which is very remarkable for its posteriorly widened abdomen, terminated by two long arcuated spines: it inhabits Java. These spinous species might form a peculiar subgenus. (2) The Jlr. pilipes, clavipes, &c, of Fabricius. His Jlr. maculata forms the genus Ncphisu, Leach. See the Tab. and Hist, des Aran, of Walckenaer. PULMONARIiE. 191 We now come to Spiders that are sedentary, like the preceding, but which have the faculty of moving sideways, forwards and back- wards, in a word, in all directions. They constitute our section of the Laterigrad^:. The four anterior legs are always longer than the others; sometimes the second pair surpasses the first, and at others, they are nearly equal; the animal extends them to the whole of their length on the plane of position. The chelicerse are usually small, and their hook is folded trans- versely, as in the four preceding tribes. Their eyes, always eight in number, are frequently very unequal, and form a segment of a circle or crescent; the two posterior lateral ones are placed farther back than the others, or are nearer to the lateral margin of the tho- rax. The jaws, in most of them, are inclined on the lip. The body is usually flattened, resembling a crab; the abdomen is large, round- ed, and triangular. These Arachnides remain motionless on plants, with their feet extended. They make no web, simply throwing out a few solitary threads to arrest their prey. Their cocoon is orbicular and flat- tened. They conceal it between leaves, and watch it until the young ones are hatched. Micrommata, Lat. Sparassas, Walck. Jaws straight, parallel and rounded at the end; eyes arranged four by four, on two transverse lines, the posterior of which is longest, and arcuated backwards. The second legs, and then the first, are the longest; the ligula is semicircular(l). Microm. smaragdula; Ar. smaragclula, Fab.; Jir. viridissima, De Geer; Clerck, Aran. Suec. pi. 6, tab. iv. A medium size; green; the sides edged with light yellow; abdomen greenish yellow, intersected on the middle of the back by a green line. It ties three or four leaves in a triangular bundle, lines the interior with a thick layer of silk, and places its cocoon in the middle; the latter is round, white, and so diaphanous, that the ova can be perceived through its parietes. The eggs are not agglutinated. M. Argelas; Dufour, Ann. des Sc. Phys., VI, p. 306, XCV, I; Walk., Hist, des Aran., IV, ii. This animal, whose specific ap- pellation will remind the French naturalists of one of their most (1) M. Walckenaer places this genus in that series which is composed both of the Vagabundse and the Sedentarix, such as the Jlttas or our Saltici, the Thomisi, Philodromi, Drassi, and Clubiona;, and which have but two hooks to the tarsi. 192 ARACHNIDES. zealous savans, one already recommended by me to their esteem as my protector from the horrors of the revolution, is one of the largest species indigenous to Franeej M. Dufour has completed my description of it, and has observed its habits. The body is about seven or eight lines in length, of a cinereous flaxen colour, covered with down, and more or less spotted with black. The top of the abdomen, from its middle to the extremity, is mark- ed with a band formed of a series of small hatchet-shaped spots, of the last mentioned colour. A black longitudinal band, grey in the middle, runs along its under surface. The legs are annu- lated with black. This species was discovered by the naturalist to whom I have dedicated it, in the environs of Bourdeaux. M. Dufour has since found it in the most barren mountains of Va- lencia. It runs with great velocity, the feet being extended late- rally. Its unguiculated palettes enable it to cling to the smooth- est surface, and in every possible position. It constructs a cocoon, which in texture resembles that of the Clotho of Durand, on the under surface of stones, to which it retires for shelter in bad weather, to escape from enemies, and to lay its eggs. It is an oval tent, nearly two inches in diameter, attached to the 6tone in the manner of a marine Patella. It is formed of an external envelope, consisting of a yellowish taffeta, as line as the peel of an onion, but rigid, and of an inner lining which is more supple, softer, and open at both ends. It is from these openings, which are furnished with valves, that the animal issues. The cocoon is globular, and placed underneath its dwelling, so that it can brood over it$ it contains about sixty eggs. The same naturalist has described and figured another spe- cies, the M. a tarses spongieux Ann. des Sc. Phys., V, lxix, 6 which he found on a tree in a garden at Barcelona. From its habits, however, and some of its characters, I presume that it belongs to the genus Philodroma of Walckenaer(l). Senelops, Duf. The Senelopes form the transition from the preceding genus to the following one. The jaws are straight or but slightly inclined, (1) For the other species, see the Tab. des Aran., Walck., and his Hist, des Aran , fascic. IV, Sparassus roseus, X, the male; lb., fascic. II, viii, the male. I think we should refer to this subgenus the Jlranea venatoria, L., Sloane's Hist, of Jam., CCXXV, 1, 2; Nhamdiu, 2? Pison; and another species-from India very- analogous to the preceding, figured on Chinese drawings and paper-hangings. PULMONAUI/K. 193 without any lateral sinus, and taper to a point obliquely truncated on the inner side. The ligula is semicircular like that of the Mi- crommatae, but the eyes are arranged differently. There are six before forming a transverse line; the two others are posterior, and situated one on each side, behind each extremity of the preceding line. The legs are long; the second pair, and then the third and fourth, are longer than the first. The type of the genus, Senelops omalosoma, Dufour, Ann. des Sc. Phys. V, Ixix, 4, was found by M. Dufour in Valencia, but it is very rare there. The body is about four lines in length and very flat, of a greyish red, with cinereous spots; the feet are annulated with black. The posterior part of the abdomen seems to exhibit vestiges of annuli, forming on the sides an ap- pearance of teeth. It lives among rocks, and when escaping from pursuit flies with the rapidity of an arrow. It is also found in Syria Collection of M. Labillardiere and in Egypt. Other species inhabit Senegal, the Cape of Good Hope and the Isle of France. Philoduomus, Walck.(l) The Philodromi differ from the two preceding subgenera in their jaws, which are inclined on the ligula, which is also higher than it is wide. The almost equal eyes always form a crescent or semi- circle. The lateral ones are never placed on tubercles or eminences. The chelicerae are elongated and cylindrical; the four or two last legs do not materially differ in length from the others. According to Walckenaer these animals run with great swiftness, their legs extended laterally, lie in wait for their prey, throw out solitary threads to entrap it, and conceal themselves in crevices or among leaves. In some the body is broad and flat, the abdomen short and widened posteriorly, and the four intermediate legs the longest. Such is the Philo drome tigree; Thomise tigre, Lat.; Araneus margurilarius, Clerck, VI, iii; Schseff., Icon., lxxi, 8; Frisch, Ins., Centur., II, xiv; Aranea levipes, L. ? It is about three lines in length. Its two anterior intermediate eyes and the four lateral ones are situated on a slight elevation, and the lat- ter, according to the same naturalist, are somewhat the largest, or at least are more apparent. The thorax is very wide, flat- tened, of a reddish fawn colour, brown laterally and posteriorly, (1) In the first edition of this work, this subgenus formed our first division of the Thomisi. Vol. III. Z 194 ARACHNIDES. and white anteriorly. The abdomen, which forms a kind of pentagon, is speckled by the red, brown and white hairs which cover it, and edged laterally with brown; there are four or six impressed points on the middle of the back. The belly is whitish, and the legs are long, slender and reddish, with brown spots. This species is very common on trees, wooden partitions, walls, &c, where it remains as if glued, with the feet extended. If touched, it runs with astonishing rapidity, or falls to the ground supported by a thread. The cocoon is of a beautiful white, and contains about a hundred eggs, which are yellow and free. The female places it in hollows of trees or clefts of posts, Sec, exposed to the north, and carefully watches it. The other Philodromi, which, according to the method of M. Walckenaer, form several small groups, have the body, and some- times the chelicerae, proportionably longer. The abdomen is some- times pyriform or ovoid, and sometimes cylindrical. The second pair of legs and then the first or the fourth are the longest. Philodromus rombiferus, Walck., Faun. Franc, Aran., VI, 8, the male. Its body is three lines and a half in length and reddish; the second legs and then the two last are the longest; sides of the thorax brown; the abdomen ovoid, with a black or brown lozenge-shaped spot above, bordered with white. Philodromus oblongus, Walck., lb., tab. ead., fig. 9. This species, as respects the relative proportion of the legs, and the disposition of the eyes, belongs to the same division; but the abdomen is longer and almost cylindrical or forming an elon- gated cone, with three brown longitudinal streaks and points on a yellowish ground, which is also the colour of the thorax. In the middle of the latter are two brown streaks forming an elongated V. Th.ese two species inhabit the environs of Paris. For the other, see the Faune Franeaise, from which we have extracted the preceding descriptions. Thomisus, Walck. The Thomisi differ from the Philodromi in their chelicerae, which are smaller in proportion and cuneiform, and in their four posterior legs, which are evidently and even suddenly shorter than the pre- ceding ones. The lateral eyes are frequently situated on eminences, while those of the Philodromi are always sessile. Here also the two posterior lateral ones are further behind than the two that are inter- mediate on the same line, while in the Thomisi these four eyes are nearly on a level. PULMONAltliE. 195 The species of this genus are those more particularly designated by the name of Crab-Spiders. The males frequently differ greatly from the females in colour and are much smaller. Some of them, all exotic(l), have their eyes arranged four by four on two transverse and almost parallel lines, the posterior of which is the longest. In the others, and the greater number, the ensemble of these eyes represents a crescent, the convex side of which is forwards and out- wards. Thomisus globosus; Jlranea globosa, Fab. ; Jlranea irregularis, Panz., Faun. Insect. Germ, fascic. LXXIV, tab. xx, female; Walck., Faun. Franc, Aran., VI, 4. Three lines long; black; abdomen globular; red or yellowish all round the back. Thomisus crisfatus; Clerck, Aran. Suec, pi. 6, tab. vi, size of the preceding; body grey-reddish, sometimes brown, with scattered hairs; feet with small spines; lateral eyes largest and placed on a tubercle; a transverse yellowish stripe on the front of the thorax; two others of the same colour on the back forming a V; abdomen rounded, and a yellowish band on the middle of the back with three indentations on each side. A common species frequently observed on the ground. Thomisus citreus', Jlranea citrea, De Geer; Schaeff. Icon. In- sect., tab. xix, 13. A lemon yellow, with a large abdomen wider- behind; two red or saffron coloured streaks or spots are frequently observed on the back. On flowers(2). A subgenus established by M. Walckenaer, under the name of STORENA,but which is yet but imperfectly known, should apparently terminate this section and lead to Oxyopes, which are as nearly allied to the Crab-Spiders as to the Citigradse. The Storenae have their jaws inclined on the ligula, which is nearly of the same length, and forms an elongated triangle; the chelicerse are conical; the two ante- rior legs, and then the second, longest; the two following ones longer than the last. The eyes are arranged in three transverse lines, 2, 4, 2; the posterior, with the two intermediate ones of the second lines, form a small square, and the two anterior ones are distant(3). Other Aranese whose eyes, always eight in number, extend more. (1) Thomisus Lamarck, Lat, a species allied to the Jlranea nohilis, Fab.; T. canceridus, Walck., ejusd.; T. leucosia,- Jlranea regia? Fab.; T. plagusius,- T. pinnotheres. (2) See the Tab. des Aran., Walck.; the Faune Franc, Id., and the Ann. des Sc. Phys., for the Spanish species described by M. Dufour, see also Nouv. Diet. d'Hist. Nat. second edition, article Thomise. (3) See Tab. des Aran., Walckenaer, IX, 85, 86. " 196 AUACHNIDES. along the length of the thorax, than across its breadth, or at least almost as much in one direction as the other, and which form either a truncated curvilinear triangle or oval, or a quadrilateral, constitute a second general division, or the Vagabundje, which I have thus named to distinguish them from those of the first, or the Sedentariae. Two or four of their eyes are frequently much larger than the others; the thorax is large, and the legs robust; those of the fourth pair and then the two first, or those of the second pair, are usually the longest. They make no web, but watch for their prey and seize it, either by hunting it down, or by suddenly leaping upon it. We divide them into two sections. The first, that of the Citigrad/e, is composed of the Araignees- Loups of authors. The eyes form either a Curvilinear triangle, an oval, or a quadrilateral, of which, however, the anterior side is much narrower than the widest part of the thorax. This part of the body is ovoid, narrowed before, and carinated along the middle of its length. The legs are usually only fit for running. The jaws are always straight, and rounded at the end. Most of the females remain on their cocoon, or carry it with them at the base of the abdomen, or suspended to the anus. Nothing but the most extreme necessity will induce them to abandon it, and when the danger is over, they always return in search of it. They also take care of their young for a certain period after they are hatched. Oxyopes, Lat. Sphasus, Walck. The eyes arranged two by two, on four transverse lines, the two extreme ones the shortest; they describe a sort of oval, truncated at each end. The ligula is elongated, narrowest at base, dilated and rounded towards the end. The first pair of legs is the longest; the fourth and second are nearly equal; the third is the shortest(l). Ctenus, Walck. The eyes arranged in three transverse lines, which become gra- dually longer 2, 4, 2 and form a sort of curvilinear, reversed tri- angle, with a truncated apex. The ligula is square, and almost iso- metrical; the fourth pair of legs, and then the first, are the longest; the third is the shortest. (1) Sphasus heterophthalmus, Walck., Hist, des Aran. fasc. Ill, tab. viii, female; Oxyopes variegatus, Lat.; Sphasus italicus, Walck., lb., Fasc. IV, tab. viii, female; Oxyopes Uncut us, Lat., Geneiv Crust, et Insect., I, v, 5, female. See article Oxyope, in the entomological part of the Kncyclop. Method., the Tab. des Aran., Walck., and the Faune Francaiso PULMONARY. 197 This genus was established on a large species found at Cayenne. Others have since been discovered in the same island and in Brazil, but none of them have been described. Dolomedes, Lat. The eyes, arranged in three transverse lines, 4, 2, 2, form a quad- rilateral, somewhat wider than long; the two posterior ones are placed on an elevation. The second pair of legs is as long as or longer than the first; those of the fourth are still longer. The ligula is square and as broad as it is high, like that of a Ctenus. In some, the two lateral eyes of the anterior line are larger than the two intermediate ones; their abdomen is an oblong oval termi- nating in a point. The females construct an infundibuliform, silky nest on the tops of trees covered with leaves, or on bushes; there they lay their eggs, and when they go abroad to hunt or are forced to abandon their retreat, they always bear off their cocoon which is attached to the base of the abdomen. Clerck says he has seen them spring upon flies which were buzzing around them(l). They inhabit the borders of streams, run over their surface with the most surprizing rapidity, and can even partly enter the water without becoming wet. The females weave a coarse irregular web, between the branches of plants, in which they place their cocoon. They watch.it till the ova are hatched(2). Lycosa, Lat. The eyes of the Lycosae also form a quadrilateral, but one as long or longer than it is wide; the two posterior eyes are not placed on an elevation. The first pair of legs is evidently longer than the se- cond, but shorter than the fourth, which, in this respect, surpasses all the others. The internal extremity of the jaws is obliquely truncated. The ligula is square but longer than it is broad. Almost all the Lycosae keep on the ground, where they run with great swiftness. They inhabit holes accidentally presented to them, or which they excavate, lining their parietes with silk, and enlarging them in proportion to their growth. Some establish their domicil (1) Araneus mirabilis, Clerck, Aran. Suec, pi. v, tab. 10; Aran, rufo-fasciata, De Geer; Ar. obscura, Fab. See the Faune Francaise Dolomedes sylvains and the Ann. des Sc. Phys. Dolomede spinimane, Dufour, V, Ixxvi, 3. (2) Dolomedes marginatus, Walck.; Araneus undatus, Clerck, V, tab. 1; De Geer, Insect. VII, xvi, fig. 13, 15; Panz., Faun., LXXI, 22; Dolomedes fimbriatus, Walck.; De Geer, Insect. VII, xvi, 9 11; Araneus fimbriatus, Clerck, V, tab. ix. These species compose the division of the shore Dolomedes of Walckenaer. 198 ARACHNIDES. in chinks and cavities in walls, where they form a silken tube co- vered externally with particles of earth or sand. In these retreats they change their tegument, and, as it appears, after closing the opening, pass the winter. There also the females lay their eggs. When they go abroad they carry their cocoon with them, attached to the anus by threads. On issuing fuom the egg the young ones cling to the body of the mother and remain there until they are able to provide for themselves. The Lycosse are extremely voracious, and courageously defend their dwelling. A species of this genus, the Tarentula, so called from Taren- tum, a city of Italy, in the environs of which it is common, is highly celebrated. The poisonous nature of its bite is thought to produce the most serious consequences, being frequently fol- lowed by death or Tarentism, results which can only be avoided by the aid of music and dancing. Well informed persons, how- ever, think it more necessary in these cases to combat the ter- rors of the imagination than to apply an antidote to the poison; medicine at all events presents other means of cure. Several curious observations on the Lycosa tarentula of the south of France have been published by M. Chabrier, Acad, de Lille, fascic. IV. This genus is very rich in species, which have not as yet, how- ever, been well characterized. Lye. tarentula; Aranea tarentula, L., Fab.; Albin, Aran., tab. xxxix; Senguerd. de Tarent. An inch long; under part of the abdomen red, crossed in the middle by a black band. The Tarentula of the south of France Lycose narbonnaise, Walck., Faun. Franc., Aran., I, 1 4, is not quite so large; the under part of its abdomen is very black and edged all round with red. A similar species is found in the environs of Paris, the Lyeose ouvriere, or L. fabrilis, Clerck, Aran. Suec, pi. 4, tab. ii; Walck., Faun. Franc., Aran., II, 5. Lye. saccata; Aranea saccata, L.; Araneus amentatus, Clerck, IV, tab. viii; Lister, tit. 25, f. 25. Small; blackish; carina of the thorax, obscure reddish, with a cinereous line; a little bundle of grey hairs at the superior base of the abdomen; legs of a livid red, varied with blackish spots; the cocoon flat and greenish very common about Paris(l). (1) For the other species see the Tabl. and Hist, des Aran, of Walckenaer, and the Faune Frangaise, Aran., Id. See also the second edition of the Nouv. Diet. d'Hist. Nat, article Lycose. PULMONARIiE. 199 We will terminate this section with the subgenus Mvrmecia, Lat., Which seems to lead to the following one, and whose characters we have detailed in the Ann. des Sc. Nat., Ill, p. 27. The eyes form a short and broad trapezium? there are four before in a transverse line; two others, more internal than the two last of the preceding ones, form a second transverse line; the last two are behind the two preceding ones. The chelicerae are stout. The jaws are rounded and very hairy at the end. The ligula is nearly square; somewhat longer than broad. The legs are long, and almost filiform; those of the fourth and first pairs are the longest of all. The thorax seems to be divided into three parts, of which the anterior is much the larg- est and square, the two others resemble knots or humps. The abdo- men is much shorter than the thorax, and is covered with a solid epidermis, from its origin to the middle. The Myr. fulva, on which I have established this genus, inha- bits Brazil; other species however appear to be found in Geor- gia, United States of America. In the second section of the Vagabundae, that of the SaltigradjE, called by others Jlraignees phalanges, the eyes form a large quadrila- teral, the anterior side of which, or the line formed by the first ones, extends across the whole width of the thorax; this part of the body is almost square or semi-ovoid, plane or but slightly convex above, as wide anteriorly as in the rest of its extent, and descending sud- denly on the sides. The legs are fitted for running and leaping. The thighs of the two forelegs are remarkable for their size. The Araignee a chevrons blancs of Geoffroy, a species of Sal- ticus very common in summer on walls or windows exposed to the sun, moves by jerks, stops short after a few steps and raises itself on its fore legs. If it discover a fly, or particularly a musquito, it approaches softly, and then darts upon the victim with a single bound. It leaps fearlessly and perpendicularly on a wall, being always attached to it by a thread, which lengthens as it advances. This same filament also supports it in the air, enables it to ascend to its point of departure, and allows it to be wafted by the wind from one place to another. Such, gene- rally, are the habits of the species that belong to this division. Several construct nests of silk resembling oval sacs open at both ends, between leaves, under stones, Sec. Thither they re- tire to change their tegument and to seek shelter in bad weather. If danger menaces them there, they leave it at once and escape with speed. The females construct a sort of tent, which becomes the 200 ARACHNIDES. cradle of their posterity, and in which the young ones, for a time, live in common with the mother. Certain species, resembling Ants, elevate their anterior legs and make them vibrate with great rapidity. Singular combats sometimes ensue between the males, but no fatal issue occurs. A subgenus established by M. Rafinesque, that of Tessarops, Appears to us to approximate closely to the following one in most of its characters and habits, but to be widely removed from it, if there be no mistake, in the number of the eyes which is but four. See Ann. Gener. des Sc. Phys., VIII, p. 88. A second subgenus, which also is only known to us by description, is the Palpimanus, Duf., Described by M. Dufour in the Ann. des Sc. Phys., V, Ixix, 5, and which appears to him to be intermediate between Eresus and Salticus. The disposition of the eyes is about the same as in the first of these two subgenera. The ligula is similarly triangular and pointed, and the jaws are still dilated and rounded at the end; but according to M. Dufour, they are inclined and not straight like those of the Eresi. The terminal joint of the anterior tarsi is in- serted laterally and has no hooks. He describes one species, the Palpimane bossu. It never jumps, walks slowly, and is found under stones in Valencia, where, however, it is extremely rare. A new species has been discovered by M. Lefevre in Sicily, which appears to me to belong to this genus. In the two following subgenera there are always eight eyes; the jaws are straight. Eresus, Walck. Four eyes forming a small trapezium near the middle of the ante- rior extremity of the thorax, the other four on its sides forming a similar but much larger figure. The ligula is triangular and point- ed. The tarsi are terminated by three hooks(l). (1) Eresus cinnaberinus, Walck.; Jlranea quatuor -guttata, Ross., Faun. Etrusc, II, 1, 8, 9; Coqueb., lllust. Icon. Insect., dec. HI, xxvii, 12; Aranca nigra, Petag\, Specim. Insect. Calab. M. Dufour, Ann. des Sc. Phys., has described two Spanish species; one of them the Eresus acanthophilus VI, xcv, 3, 4 is my Erese raye of PULMONARIiE. 201 Salticus, Lat. Jlttus, Walck. Four eyes, the two intermediate of which are the largest, on the anterior part of the thorax in a transverse line, and the others near its lateral edges, two on each side; they also form a large square open behind, or a parabola. The ligula is very obtuse or truncated on the summit. There are but two hooks to the extremity of the tarsi. Several of the males have very large chelicerae. The thorax of some is very thick and sloping, (en talus) and much inclined at base. Salt. Sloanei; Jlranea sanguinolenta, L. Black; a white line formed by down on each side of the thorax; the abdomen of a cinnabar-red, with an elongated black spot on the middle of the back. South of France, on stones(l). The thorax of the others is much flattened, insensibly sloping at its base. Sometimes their body is simply oval, and furnished with hairs or thick down; the legs short and robust. Saltique chevronne; Jlranea scenica, L.; Jlraignee a chevrons, Geoff".; Jlraignee a bandes blanches, De Geer, Insect., VII, xvii, 8, 9. About two lines and a half long; above, black; margin of the thorax, and three lines en chevron on the top of the ab- domen, white. Very common(2). Sometimes the body is narrow, elongated, almost cylindrical and shorn ; the legs long and slender. Salt, formicarius; Jlranea formicaria, De Geer, Insect., VII, xviii, 1, 2; Jltte fourmi, Walck., Faun. Franc., Aran., V, 1 3. Reddish; fore part of the thorax black; black band and two white spots on the abdomen(3). the Nouv. Diet. d'Hist. Nat.; the other, Eresus imperialis V, lxix, 2 is closely allied to the JLranea nigra, Petagna, above quoted. These two species are figured in the Faune Frangaise, Aran., pi. IV, 3, 4, 5. See also on same plate, fig. 7, the Erese cinabre. ( 1 ) This division comprizes the following Atti of Walckenaer: bicolor, chaly- beus, niger, cupreus, muscorum, the Jlranea gossipes, De Geer. (2) Add, Jlttus tardigradus, Walck., Hist, des Aran., V, iv, female. See his Tabl. des Aran. (3) For the remaining species of this subgenus, see the Aran, of the Faune Frangaise. M. Walckenaer, author of that portion of the work, in his Tabl. des Aran., mentions a species enclosed in amber. Vol. III. 2 A 202 AUACHNIDES. FAMILY II. PEDIPALPI. In the second family of the Arachnides Piilmonariae, we find very large palpi, resembling projecting arms, terminated by a forceps or a claw; didactyle cheliceras, one finger of which is movable ; an abdomen composed of very distinct segments, without fusi at the extremity ; and the sexual organs placed at the base of the abdomen. The whole body is invested with a firm tegument ; the thorax consists of a single piece, and exhibits three or two simple eyes, approximated or grouped, near the anterior angles ; and near the middle of its anterior extremity, or posteriorly, but in the median line, two others equally simple and approximated. There are four or eight pulmonary sacs. Those which form the genus Tarantula, Fab., Have their abdomen attached to their thorax by a pedicle, or por- tion of their transverse diameter; it has no pectinated laminae at its base, nor sting at its extremity. Their stigmata, four in number, are situated near the origin of the venter, and are covered with a plate. Their chelicerse (mandibles) are simply terminated by a movable hook. Their ligula is elongated, very narrow, and con- cealed. They have but two jaws, which are formed by the first joint of their palpi. They all have eight eyes, of which three, on each side and near the anterior angles, form a triangle; and two near the middle at the anterior margin are placed on a common tubercle or little elevation, one on each side. The palpi are spinous. The tarsi of the two anterior legs differ from the others, being formed of numerous seta- ceous or filiform joints, and without a terminal nail. They are confined to the hottest portions of Asia and America. Their habits are unknown to us. They now constitute two subge- nera. Phhynus, Oliv. Palpi terminating in a claw; the body much flattened; thorax broad, and almost in 1 the form of a crescent; abdomen ecaudate, and PULMONARY. 203 the two anterior tarsi very long and slender, resembling setaceous antennae(l). Thelyphonus, Lat. The Thelyphoni are distinguished from the preceding subgenus by their shorter, thicker palpi, terminated by a forceps or by two united fingers; by their long body with its oval thorax, and the ex- tremity of the abdomen furnished with an articulated seta forming a tail. Their anterior tarsi are short, of a uniform appearance, and composed of few articulations(2). The others have their abdomen intimately united to the thorax throughout its entire width, presenting, at its inferior base, two movable pectiniform laminae, and terminated by a knotted tail armed with a terminal sting. Their stigmata, eight in number, are exposed, and arranged four by four along the belly ; their chelicerae are terminated by two fin- gers, of which the exterior is movable. They form the genus Scorpio, Lin., Fab. Scorpions have an elongated body, suddenly terminated by a long slender tail formed of six joints, the last of which terminates in an arcuated and excessively acute point or sting, which affords issue to a venomous fluid contained in an internal reservoir, forming a long square, and usually marked in the middle by a longitudinal sulcus, presenting on each side, and near its anterior extremity, three or two simple eyes, forming a curved line, and near the middle of the back two others, also. simple, which are approximated. The palpi are very large, with a forceps at the extremity resembling a hand; their first joint forms a concave and rounded jaw. There is a tri- angular appendage at the origin of each of the four anterior legs, which (appendages) by their approximation have the appearance of a quadripartite lip; the two lateral divisions, however, may be con- sidered as a kind of jaws, the remaining two forming the ligula. (1) Phalangium reniforme, L.; Pall. Spic. Zool. fascic. IX, iii, 5, 6; Herbst. Monog. Phal., Ill; East Indies, the Sechelles; Herbst., lb., IV, 1, South America; Tarantula reniformis, Fab.; Pall. Spic. Zool., IX, iii, 3, 4; Herbst. lb. V, 1; ejusd. IV, 2, var.? the Antilles. . (2) Phalangium caudatum, L.; Pall. Spic. Zool- fascic. IX, iii, 1, 2, from Java. South America produces another species described and figured in the Jour, de Phys. et d'Hist. Nat., 1777; the inhabitants of Martinique call it the Vinaigrier. A third species, smaller than the preceding ones, and with fulvous feet, inhabits the peninsula beyond the Ganges. 204 ARACHNIDES. The abdomen is composed of twelve annuli, those of the tail included,' the first is divided into two parts, of which the anterior bears the sexual organs, and the other the two combs. These appendages are composed of a principal, narrow, elongated and articulated piece, movable at base, and furnished along its inner side with a suite of little hollow laminae, united to it by an articulation, that are nar- row, elongated, parallel, and similar to the teeth of a comb; their number is more or less considerable according to the species; it varies to a certain extent, and perhaps with age, in the same spe- cies. No positive experiment has yet determined the use of these appendages. The four following annuli have each a pair of pulmo- nary sacs and stigmata. Directly after the sixth, the abdomen becomes suddenly narrowed, and the remaining six, under the form of joints, compose the tail. All the tarsi are alike, and consist of three joints, with two hooks at the end of the last. The four last legs have a common base, and the first joint of the hip is soldered; the two last are even partly fixed against the abdomen. The two nervous cords, proceeding from the brain, unite at in- tervals and form seven ganglions, the last of which belong to the tail. In all other Arachnides, there are never more than three. The eight stigmata open into as many white bursae, each contain- ing a great number of very slender, small laminae, between which it is probable that the air passes. A muscular vessel extends along the back, and communicates with each bursa by two branches(l); it also distributes vessels to every part of the animal. The intestinal canal is straight and slender. The liver is composed of four pairs of glandular clusters, which pour their humour into the intestine at four points. The male has two copulating organs arising near the combs, and the female has two vulvae. The latter open into a matrix consisting of several inter-communicating canals, which in the proper period are found filled with living young ones; the testes are also formed of some anastomosing vessels(2). These Arachnides inhabit the hot countries of both hemispheres, live on the ground, conceal themselves under stones and other bo- dies, most commonly in ruins, dark and cool places, and even in houses. They run with considerable swiftness, curving their tail over their back. They can turn it in every direction, and use it for the purposes of attack and defence. With their forceps they seize (1) See our preceding remarks on the circulation of the Arachnides Pulmo- narix. (2) For the anatomy of* the Scorpion, see Treviranus, Marcel de Serres, and Leon Dufour, Journ. de Phys., June 181T. PULMONARI/E. 205 Onisci and various insects, Carabici, Orthoptera, &c, on which they feed, pierce them with their sting by directing it forwards, and then pass their prey through their chelicerae and jaws. They are particularly fond of the eggs of Spiders and of Insects. The wound occasioned by the sting of the europseus is not usually dangerous. That of the Scorpion of Souvignargues, of Maupertius, of the species which I have named Roussatre (occitanus), and which is larger than the preceding one, according to the experiments of Dr Maccary courageously tried upon himself, produces serious and alarming symptoms; the older the animal the more active seems to be the poison. The remedy employed is the volatile alkali, used externally and internally. Some naturalists have asserted that the European species produce two generations in the year. That which appears to me to be the most unequivocally ascertained, occurs in August. The female in coitu is laid on her back. According to Maccary she changes her tegument previous to the production of her young. The male ex- periences a similar alteration at the same epoch. The young are produced at various intervals. The mother car- ries them on her back for several days, during which time she never leaves her retreat, and watches over them for a month, when they are strong enough to establish themselves elsewhere and provide for their subsistence. Two years are required to qualify them for con- tinuing their species. Some have eight eyes; they form the genus Buthus of Leach. S. afer, L., Fab.; African Scorpion, Roes., Insect., 3, Ixv; Herbst. , Monog. Scorp., 1. Five or six inches long, and of a blackish brown; the forceps large, cordate, rough and some- what hairy; anterior edge of the thorax deeply emarginate; thirteen teeth to each comb. From the East Indies, Ceylon. S. roussatre; S. occitanus, Amor.; S. tunetanus, Herbst. Monog. Scorp. Ill, 3; Buthus occitanus, Leach, Zool. Miscell., cxliii. Yellowish or reddish; tail rather longer than the body, with elevated and finely crenulated lines. Upwards of twenty- eight teeth fifty-two to sixty-five, Maccary to each comb. From the south of Europe, Barbary, Sec. Very common in Spain. The others have but six eyes; they compose the genus Scorpio, properly so called, of the same naturalist. S. europasus, L., Fab.; Herbst. Monog. Scorp., Ill, 1, 2. Brown, more or less dark; legs and last joint of the tail paler or yellowish; forceps cordate and angular; nine teeth to each comb. From the extreme southern and eastern departments of France. 206 ARACHNIDES. ORDER II. TRACHEARItE. The Arachnid es which compose this order differ from those of the preceding one in their organs of respiration, which consist of radiated or ramified trache(l), that only receive air through two stigmata; in the absence of an organ of circu- lation^) ; and in the number of their eyes, which is but from (1) The trachese are vessels which receive the aerial fluid and distribute it to every part of the interior of the body, and thus remedy the want of circulation. They are of two kinds. Those that are tubular or clastic are formed of three membranes, the intermediate of which is composed of a cartilaginous elastic fila- ment spirally contorted; the two others are cellular. The vesicular trachea: consist of but two membranes of the latter description. They are a kind of pneumatic pouches susceptible of being inflated and depressed. Aquatic Insects, and others that are aerial, are deprived of them. They communicate with each other by tubular tracheae. In several of the Orthoptera, where they are well developed, cartilaginous arches, formed by appendages of the inferior semi-annuli of the abdo- men, give points of attachment to the muscles which form them. The branchiae are divided into two principal trunks which extend longitudinally throughout the body, one on each side, receiving air through lateral openings or stigmata, and then throwing off" numerous branches and twigs which disti'ibute it. In several Insects, however, there are two other trunks more or less long, situated between the two preceding ones and communicating with them. M. Marcel de Serres distinguishes them by the term pulmonary trachese: the others he calls arterial trachex. He also distinguishes two sorts of stigmata: one kind, or the ordinary stigmata, simple, and consisting of two membranous lips, furnished with trans- verse stria: or fibres, and opening merely by contraction; the others, which he calls tremaeres, are formed of one or two (usually two) horny, movable pieces, opening and closing like shutters. De Geer Descript., Gryllus migratorius compares them to eye-lids. They are peculiar to certain Orthoptera, and their position shows them to be the stigmata of the mesothorax. M. Leon Dufour Ann. des Sc. Nat., May 1826 has given excellent figures of these various kinds of stigmata, but without employing the names of the preceding authors. It would appear from his description of the abdominal stigmata, that they have the charac- ters of the tremaeres, while those which he afterwards describes as different, are the ordinary stigmata. Our own opinion is that these differences are mere simple modifications of the lips. Reaumur, Mem., I, iv, 16, has figured a stigma of this latter kind, where the lips have an internal border, which, from all appearances, must be corneous. By supposing them to be almost entirely of this nature, we have the tremaere of M. de Serres. Certain aquatic larva: have a peculiar respi- ratory apparatus, of which we shall speak hereafter. (2) The presence of trachese excludes a complete circulation, that is to say, TRACHEA UliE. 207 two to four(l). The want of sufficiently general anatomical observations, has prevented the limits of this order from being rigorously determined. Some of these Arachnides, the Pycnogonides for instance, exhibit no stigmata; their mode of respiration is unknown. The Trachearise are very naturally divided into those which are furnished with chelicera?, terminated by two fingers, one of which is movable, or by one that is equally so; and into those where these organs are replaced by simple laminae, or lancets, which with the ligula constitute a sucker. Most of these animals, however, being very small, great difficulties necessarily accompany these investigations, and it is readily perceived that such characters should only be resorted to when it is impossible to avoid it. FAMILY I. PSEUDO-SCORPIONES. In this family we find the thorax articulated, its first seg- ment much the largest, and resembling a corselet ; the abdomen is very distinct and annulated, and the palpi very large and in the form of legs or claws. There are eight legs in each sex, with two equal hooks at the extremity of the tarsi, the two anterior ones, at most, excepted, and two apparent chelicerse terminated by two fingers and two toes, formed by the first joint of the palpi. They are all terrestrial, and have an oval or oblong body. This family comprehends but two genera. the distribution of the blood to the different parts of the body, and its return from the organs of respiration to the heart. Thus, although some vessels have recently been discovered in certain Insects Phasma: and, although they may possibly exist in various Arachnides Trachearise, it does not exclude them from the general system. M. M. de Serres has observed that the intestinal tube of the Phalangium gives off numerous caeca or vermiform appendages, which seem to have some analogy with the hepatic vessels, and that the tracheae ramify over them ad infi- nitum. (1) According to Mullcr the Hydrachuu umbrata has six eyes: but may this not have arisen from an optical illusion or some mistake? 208 ARACHNIDES. Galeodes, Oliv. Solpuga, Licht., Fab. Two very large chelicerae, with strongly dentated vertical fingers, one superior, fixed, and frequently furnished at its base with a slender, elongated, pointed appendage(l), and the other movable; large pro- jecting palpi in the form of feet or antennae, terminated by a short, vesicular joint, resembling a button without a terminal hook; the two anterior feet of an almost similar figure, equally unarmed, but smaller; the others terminated by a tarsus, the last joint of which is furnished at the end with two little pellets, and two long toes termi- nated by a hook; five semi-infundibuliform pediculated scales on each posterior leg, arranged in one series along their first joints; and two eyes closely approximated on an eminence anterior to the first thoracic segment, which represents a large head bearing the two anterior feet, as well as the parts of the mouth. Their body is oblong, generally soft, and bristled with long hairs. The last joint of the palpi, according to M. Dufour, contains a par- ticular organ formed like a disk, of a nacre-white, and which never protrudes unless the animal is irritated. The two anterior feet may be considered as second palpi. The labrum has the form of a little, strongly compressed, recurved rostrum, pointed and hairy at the end. The ligula is small, shaped like a keel, and is terminated by two divergent, bearded setae, each posted on a little joint. The other pairs of legs are annexed to as many segments. I have perceived a large stigma on each side of the body, between the first and second pair of legs, as well as a slit at the base of the inferior part of the abdomen. The abdomen is oval, and composed of nine annuli. It is supposed that the ancients designated these animals by the names of Phalangium, Solifuga, Tetragnatha, Sec. M. Poe disco- vered a species in the environs of Havana, but the others are pecu- liar to the hot and sandy countries of the eastern continent(2). They run with great celerity, erect their head when surprised, and show signs of resistance; they are considered venomous(3). (1) I do not think it is peculiar to either sex. (2) Our author does not seem aware of the fact that two species of this genus have been discovered by Mr Say near the Rocky Mountains: they are, 1. Gal.pal- lipes, Say. Hairy; chelicerae horizontal; fingers arcuated; abdomen sub-depressed, livid. 2. Gal. subulata, Id. Hairy; chelicerae horizontal; thumb nearly rectilinear and destitute of teeth; resembles the pallipes in form, size, and colour, but the superior finger of the chelicerx is unarmed and rectilinear, and the inferior arcu- ated with about two stout teeth. Long's Expedition, II, p. 3. Jim- Ed. (3) Solpugu fatalis, Fab.; Herbst, Monog., Solp. I, i, Bengal; #. chelicornis, TRACHEA HUE. 209 Chelifer, Geoff. Obisium, Illig. The palpi elongated, in the form of an arm, with a hand terminated by a didactyle forceps; all the legs equal, terminated by two hooks; the eyes placed on the sides of the thorax. These animals resemble small Scorpions destitute of a tail. Their body is flattened, and the thorax nearly square, with one or two eyes on each side. They run swiftly, and frequently retrograde or move sideways like Crabs. Roesel saw one female lay her eggs and collect them into a heap. Hermann, Sen. says that she carries them under her abdomen, united in a pellet. He is even of the opinion that these Arachnides can spin. Hermann, Jun. Mem. Apter. divides this genus into two sec- tions. In some Chelifer, Leach the first segment of the trunk or thorax is divided by an impressed transverse line; the tarsi consist of a single joint; there is a kind of stylet at the extremity of the mo- vable finger of the chelicerae, and the hairs of the body are shaped like a spatula. Ch. cancroides; Phalangium cancroides, L.; Scorpio cancroides, Fab.; Roes., Insect. Ill, Supp. LXIV, vulgo Book- Scorpion. Found in herbaria, old books, &c, where it feeds on the small insects that destroy them. Ch. cimicoides; Scorpio cimicoides, Fab.; Herm., Mem. Apter., VII, 9. Inhabits under bark of trees, stones, &c. In others Obisium, Leach the thorax is entire, the chelicerae are destitute of a stylet, and the hairs on the body are setaceous(l). A more important character however is found in the number of eyes. In Obisium it is four, and but two in Chelifer properly so called(2). Fab.; Herbst. Ib. ; II, 1; Phalangium araneoides, Pall., Spicil. Zool., fascic. IX, iii, 7, 8, 9. See also the Monog. of this genus by Herbst., and the Voy. of Pallas and Olivier. (1) Herm., Mem. Apter., V, 6; VI, 14. (2) See Leach, Monog. of the Scorpions, Zool. Miscell. Ill, tab. 141, 142; and a memoir on the Insects found in copal by M. Dalman, where he describes and figures a species under the name of eucarpus, and mentions several others. Vol. III. 2 B 210 AUACHNIDES. FAMILY II. PYCNOGONIDES. The trunk, in this family, is composed of four segments, occupying nearly the whole length of the body and terminated at each extremity by a tubular joint, the anterior of which is the largest, sometimes simple, and sometimes accompanied by chelicerse and palpi, or only one kind of these organs, that constitutes the mouth(l ). There are eight legs in both sexes, formed for running, but the female is furnished with two ad- ditional false ones, placed near the two anterior, and solely destined to carry her eggs. The Pycnogonides are marine animals(2), analogous either to the Cyami and the Caprellse, or to the Arachnides of the genus Phalangium, where Linnseus placed them. Their body is commonly linear, with very long legs, composed of eight or nine joints, terminated by two unequal hooks which appear to form but one, and the smallest of which is cleft. The first segment of the body, which replaces the head and mouth, forms a projecting tube, cylindrical or in the form of a trun- cated cone, with a triangular aperture at its extremity. The chelicerse and palpi are placed at its base. The former are cylindrical or linear, simply prehensile, and composed of two joints the last of which is a forceps, the inferior finger or the one that is fixed being sometimes shorter than the other. The palpi are filiform, and consist of five or nine joints, with a terminal hook. Each of the following segments, the last excepted, bears a pair of legs(3); but the first, or the one arti- (1) On the siphon of a large species of Phoxichilus brought from the Cape of Good Hope by the late M. Delalande, I observed longitudinal sutures, so that it appears to me to be composed of the labrum, ligula, and two jaws, all soldered together. In this case the palpi belong to the jaws. (2) According to Savigny they form the transition from the Arachnides to the Crustacea. We place them here, but with some hesitation. (3) M. Milne Edwards, who has investigated the anatomy of these animals on the living subject, has told me that in the interior of these organs he observed TRACHEARL