LIST OF ILLUSTRATIONS. xv 



FIG. 



PAGE 



163. Diagrammatic cross-section of an Invertebrate (Ziegler) . 331 



164. Diagrammatic cross-section of an Invertebrate (Ziegler) . 332 



165. Diagrams of insect embryo (Korschelt and Heider) . . 335 



1 66. Larva, pupa, and adult of water beetle, of blue-bottle fly, 



and of Cossus ligniperda . . . . . 338 



167. Life history of the silk-moth (Boinbyx inori] . . . 339 



168. Development of blow-fly (Calliphora erythrocephald) 



(Thompson Lowne) ....... 340 



169. Mosquito 343 



170. Scorpion .......... 348 



171. Female garden-spider ....... 352 



172. Dissection of JMygaL from the ventral surface (Cuvier) . 353 



173. Section of Lung-book (Macleod) ..... 354 



174. Follicle-mite ......... 357 



175. Itch-mite (Sarcoptes scabiei) ...... 357 



176. Limuhts or King-crab ....... 359 



177. Young Linnihis (Walcott) 360 



178. Trilobite (Conoccphalites] (Barrande) 362 



179. Vertical cross-section of a Trilobite (Calymene] (Walcott) . 362 



1 80. Sea-spider (Pycnogonum littorale) from the dorsal surface . 363 



181. Ideal mollusc (Ray Lankester) 365 



182. Stages in Molluscan development ..... 365 



183. Roman snail (Helix poinatia] ...... 366 



184. Vertical section of the shell of species of Helix . . . 367 



185. Dissection of Helix pontatia (mainly after Leuckart) . . 373 



1 86. Diagram of larva of Palndina (Erlanger) .... 374 



187. The Freshwater Mussel . 376 



1 88. Nervous system of Molluscs ...... 378 



189. Structure of Anodonta (Rankin) 380 



190. Development of Anodonta (Goette) . . . . 383 



191. External appearance of a cuttlefish ..... 385 



192. Diagram of the structure of Sepia (mainly after Pelseneer) . 389 



193. Diagram of circulatory and excretory systems in a Decapod- 



like Sepia (Pelseneer) . . . . . .391 



194. Common Buckie (Buccimtni iindatiiin} .... 393 



195. Bivalve (Panopiea iwrvegica], showing siphons . . . 394 



196. Nudibranch \Dendronotus arhorescens], showing dorsal 



outgrowths forming adaptive gills . . . . 395 



197. Ventral surface of Patella vulgata (Forbes and Hanley) . 395 



198. Chiton (Pretre) . 399 



199. Dorsal view of nervous system of Chiton (Pelseneer) . . 399 



200. Anatomy of Chiton ........ 400 



20 1. Stages in molluscan development ..... 403 



202. Proneomenia. Nervous system (Hubrecht) . . . 405 



203. Section of shell of nautilus (Lendenfeld) .... 410 



204. The Pearly Nautilus (Nautilus pompilins} (Owen) . .411 



205. Male of Balanoglossus (Dolichoghssiis] koivalevskii (Bateson) 416 



206. Transverse section through gill-slit region of Ptvchodera 



ininuta (Spengel) 4I 8 



207. Development of Balanoghssns (Bateson) . . . 419 



