LIST OF ILLUSTRATIONS xxiii 



FIG. PAGE 



177. Dicyema paradoxum, male 231 



178. Rhopalura giardii, male . 232 



179. ,, ,, female 232 



180. Salinella, longitudinal section 233 



181. ,, transverse ,, . . 234 



182. Planaria, digestive and excretory systems 237 



183. ,, nervous system 237 



184. ,, reproductive system 239 



185. Transverse section of a Planarian 240 



186. Distomum hepaticum 240 



187. ,, ,, section of integument 241 



188. ,, ,, internal organisation 242 



189. ,, ,, terminal part of reproductive apparatus . 243 



190. ,, ,, development 244 



191. Tsenia solium . 246 



192. ,, ,, head 247 



193. ,, ,, transverse section 247 



194. ,, ,, proglottis . ' 248 



195. ,, ,, ripe proglottis 250 



196. ,, ,, development 251 



197. Various Planarians 255 



198. Gunda segmentata 256 



199. Digenetic Trematodes ... 257 



200. Gyrodactylus and Polystomum 258 



201. Temnocephala 259 



202. Actinodactylella .... .260 



203. Tetrarhynchus . 261 



204. Trenia echinococcus 261 



205. Ligula ... . 262 



206. Caryophyllrcus . 263 



207. Gyrocotyle . . .... .263 



208. Archigetes 263 



209. Section of body- wall of a Triclad . .... .264 



210. Parenchyma of Flat-worm .... .... 265 



211. Diagram of Rhabdocoele 266 



212. ,, ,, Polyclad ... 266 



213. ,, ,, Triclad . . 267 



214. Flame-cell ... 269 



215. Reproductive organs of Mesostomum ehrenbergii .... 272 



216. Development of a Polyclad 274 



217. Miiller's larva ..'... 275 



218. Embryos of Denclroccelum 276 



219. Embryo of Temnocephala . 278 



220. ' 279 



221. A Cysticercoid 280 



222. ,, with head evaginated 281 



223. Cyst of Trenia echinococcus 282 



224. Scolices ,, ,, ... 282 



