LIST OF ILLUSTRATIONS. XHE 



Facing 

 page. 



217. Rictularia cristata. Female, a, two-thirds natural size; h, enlarged 170 



218. Rictularia elvirae. Anterior extremity of female 171 



219. Rictularia elvirae. Anterior extremity, showing mouth aperture 171 



220. Rictularia elvirae. Anterior extremity of female 171 



221. Rictularia elvirae. Egg 171 



222. Rictularia fallax. Posterior extremity of female 172 



223. Rictularia fallax. Anterior extremity of female, lateral view 172 



224. Rictularia coloradensis. Male 173 



225. Rictularia coloradensis. Posterior extremity of male 173 



226. Rictularia coloradensis. Latero-dorsal view of head of male 174 



227. Rictularia coloradensis. Anterior extremity of female ; v., vulva 174 



228. Rictularia coloradensis. Anterior extremity of female. ?i. r., nerve ring.. 175 



229. Rictularioides amphiacanihum. Head of female, o, lateral view; 6, view 



from the front 175 



230-233. Rictularioides amphiacanthum. 230. Female, a, natural size; b, 

 enlarged; c, portion of body. 231. Posterior extremity of female. 

 232. Posterior extremity of female, showing three rows of spines. 233. 



Profile view of cuticular spines 176 



234. Ollulanus tricuspis. Embryo 177 



235. Ollulanus tricuspis. Larval forms in muscle of mouse 178 



236-237. Filaria mortis. 236. Anterior extremity, lateral view. 237. Head, 



viewed from the front 180 



238. Filaria martis. Posterior extremity of male 181 



239. Filaria martis. Egg 181 



240. Filaria subcutanea. Posterior extremity of male 182 



241. Filaria circularis. Head, lateral view 183 



242. Filaria circularis. Posterior extremity of male lateral view 183 



243. Filaria scapiceps. Posterior extremity of male 185 



244. Filaria scapiceps. Spicules 185 



245. Filaria scapiceps. Posterior extremity of female 186 



246. Filaria scapiceps. Anteriorextremity of female, v., vulva; va^., vagina.. 186 



247. Microfilaria rosenaui 189 



248-251. Gongylonema musculi. 248. Anterior extremity of male. 249. Pos- 

 terior extremity of male. 250. Anterior extremity of female. 251. 



Posterior extremity of female 192 



252. Gongylonema neoplasticum. Posterior extremity of male, ventral view... 194 



253. Gongylonema neoplasticum. Larva from prothorax of Pcriplaneta ameri- 



cana 195 



254. Gongylonema brevispiculum. Anterior extremity 197 



255. Gongylonema brevispiculum. a, posterior extremity of male, ventral view, 



6, right spicule and gubemaculum, dorsal view 197 



256. Gongylonema brevispiculum. Vagina and ovijector. I, union of two por- 



tions of ovijector 198 



257-258. Spirura ialpae. 257. Worms attached to mucosa. 258. Anterior 



extremity, lateral view 200 



259. Spirura talpae. Posterior extremity of male 200 



260-262. Spirura talpae. 260. Anterior extremity, showing boss or struma. 



261. Posterior extremity of female. 262. a, ovijector; b, sphincter of 



ovijector 201 



263. Spirura talpae. Male larva in fourth stage, a, after the addition of acetic 



acid and separation of cuticle; 6, before addition of acid 202 



