LIST OF ILLUSTRATIONS xxi 



FIG. 



183. Trenia solium, proglottis .... . 234 



184. ,, ,, ripe proglottis . . . . 236 



185. ,, ,, development ... . ... 236 



186. Various Planarians . . ... 240 



187. Gunda segmentata . . 241 



188. Digenetic Trematodes ... . 242 



189. Gyrodactylus and Polystomum . . 243 



190. Tenmocephala . . .244 



191. Actiiiodactylella . . 245 



192. Tetrarhynchus . . 246 



193. Trenia echinococcus . . 246 



194. Ligula ... .247 



195. Caryophylheus- . . 247 



196. Amphiptyches . . ... 247 



197. Archigetes . . . .247 



198. Section of body-wall of a Triclad . . 248 



199. Parenchyma of Flat-worm .... . 249 



200. Diagram of Rhabdoc<ele ... . .251 



201. ,, ,, Polyclad . . .251 



202. ,, ,, Triclad . . 252 



203. Flame-cell . . 253 



204. Reproductive organs of Mesostomum ehrenbergii . . . 256 



205. Development of a Polyclad . . . 257 



206. Miiller's larva . . 258 



207. A Cysticercoid . . 260 



208. with head evaginated . . 261 



209. Cyst of Taenia echinococcus ... . 262 



210. Scolices ,, .262 



211. Scolex . 262 



212. Process of budding in Microstomum . ... 263 



213. Diagram of the relationships of the Platyhelminthes and NemcT- 



tinea . . . .267 



214. Diagram of Nemertine .... ... 268 



215. Tetrastemma . . 269 



216. Anterior portion of Nemertine . . . 270 



217. Proboscis of Hoplonemertean, retracted . . . 270 



218. ,, ,, everted . . 270 



219. Transverse section of Nemertine ... . 271 



220. Vascular and excretory systems of Nemertine . . 271 



221. Pilidium . . 272 



222. Ascaris lumbricoides . . 276 



223. ,, ,, transverse section . 277 



224. ,, ,, muscie fibres . 278 



225. ,, ,, dissection of female ... . 279 



226. Nervous system of Nematoda . . . . 280 



227. Ascaris lumbricoides, dissection of male organs . . 281 



228. Body-wall of platymyarian Nematode . . 283 



229. Dochmius duodenalis .... 284 



230. Transverse section of Gordius 284 



