ILLUSTRATION'S 



XV 



FIG. 

 SO 

 8l 

 82 



83 

 84 

 8S 



86 



87 



88, 

 89, 

 90. 

 91. 

 92. 



93- 

 94. 



95' 

 96. 



97- 



98. 



99. 

 roo. 

 too 

 ioi. 

 [02. 

 [03. 

 104. 

 105. 

 106. 

 [07. 

 [08. 

 109. 



10. 



11. 



12. 



13- 



14. 

 15. 

 16. 



i7- 

 18. 

 19. 



[20. 

 121. 

 [ 22. 

 [23. 



. Asterias; brachiolarian larva, ventral aspect 

 . Asterias ; brachiolarian larva, lateral aspect 

 . Pentaceros reticularis .... 

 , Ciilcita pentagularis .... 

 , Asterias vulgaris with regenerating arm 

 , Ophioglypha bullata .... 



. Istrophyton aborescefis 



Strongylocentrotus .... 



Aboral skeletal plates of sea urchin 



Diagram of spine of sea urchin 



Shell of sea urchin with spines removed 



Sea urchin with oral half of shell removed 



Arbacia punctata, larva 



Cucumaria planci 



Holothurian dissected 



Caudina arenata . 



Various Turbellaria 



) ungia aurantiaca 



Structure of a Turbellarian . 



Microstomum .... 



Distomum hepaticum, natural size 

 bis. Distomum hepaticum, anatomy 



Distomum hepaticum, development 



Development of tapeworm 



Bothriocephalic latus . 



Tcenia solium 



Scolices of various tapeworms 



Ripe proglottides of tapeworms 



Nemertes neesii 



Cerebratulus montgomeryi . 



Tetrastemma obscurum. voung 



Pilidium larva 



Micrura verrilli . 



Heterodera schachtii 



Ascaris .... 



Trichina spiralis . 



Echinorhynchus gigas and Echinorhynchus le 



Sagitta hexaptera 



Various Rotifera . 



Scrupocellaria ferox 



Bugula avkularia 



Cristatella mucedo 



Phorouis australis 



Magellania flavescens 



Magellania lenticularis 



uufi 



ornus 



9' 



92 



93 

 93 



94 



95 

 96 



97 

 98 

 98 

 99 



99 



ico 



IOI 



[02 



104 

 1 06 



[07 

 [08 

 [09 

 [09 



10 

 II 



12 

 13 



•4 

 IS 

 IS 



17 

 18 



19 

 19 



19 



[21 



[22 



23 



[24 



[2 5 



[27 



[29 

 [30 



[31 



131 



[32 



133 



