LIST OF ILLUSTRATIONS xxiii 



FIG. PAGE 



180. Dicyema paradoxum, male 229 



181. Rhopalura giardii, male .230 



182. female . 230 



183. Salinella, longitudinal section 231 



184. ,, transverse ... . . 231 



185. Planaria, digestive and excretory systems . . . 234 



186. ,, nervous system 234 



187. reproductive system . 236 



188. Transverse section of a Planarian . ... 237 



189. Fasciola hepatica ... .237 



190. ,, ., section of integument 238 



191. ,, ,, internal organisation 239 



192. ,, ,, terminal part of reproductive apparatus . . 240 



193. ,, ,, development 241 



194. Tsenia solium . . . .242 



195. head . 243 



196. ,, ,, transverse section 244 



197. proglottis . . . 245 



198. ,, ripe proglottis . . , 246 



199. ,, development 247 



200. Various Planarians . 251 



201. Gunda segmentata . . . 252 



202. Digenetic Trematodes . . 253 



203. Gyrodactylus and Polystomum . . .254 



204. Temnocephala . . 255 



205. Actinodactylella . . . 256 



206. Tetrarhynchus . 257 



207. Tsenia echinococcus . 257 



208. Ligula. . 257 



209. Caryophyllaeus . . 258 



210. Gyrocotyle. . 258 



211. Archigetes ... . 258 



212. Section of body-wall of a Triclad . . 259 



213. Parenchyma of Flat-worm . . . 259 



214. Diagram of Rhabdoccele . . . 261 

 215.- ,. Polyclad . . 261 



216. Triclacl . 262 



217. Flame-cell .... .264 



218. Reproductive organs of Mesostomum ehrenbergii . . 267 



219. Developing egg of Planocera . .269 



220. Embryo of Planocera . . 270 



221. Muller's larva of Yungia 271 



222. Embryos of Dendrocoelum . .272 



223. Embryo of Temnocephala . 273 



224. 274 



225. A Cysticercoid . . 276 



226. ,, with head evaginated . .... 276 



227. Cyst of Taenia echinococcus 



