i8o 



THE GASTROPODA 



Bergh. FAMILY 7. FIONIDAE, Alder and Hancock. Dorsal tegumentary 

 papillae provided with a membranous expansion ; liver in the form of 

 two longitudinal canals into which the caeca of the dorsal papillae open ; 

 male and female orifices at some distance from one another ; pelagic. 



PliitrophiillitUa lixeittu. A, dorsal view ; li, 

 ventral view. 6, the mouth ; 7, lamelliforni 

 pallial gills (the posterior part of the foot bears 

 a median glandular tract). (From 

 after Souleyet.) 



Fio. 168. 



lleilyle glandul(fera, dorsal aspect, e, 

 eye ; /, foot (posterior part) ; -M..S, nervous 

 system ; ph, pharynx ; sp, spicula ; r.m, 

 visceral mass. (After Kowalewsky.) 



Fio. 160. 



rmis parailoxits, 

 dorsal aspect. a, aims; nl, 

 cnidosac ; e, eye ; /, , kidney ; 

 /, liver; m, mouth (on the 

 ventral side, seen through 

 the transparent head) ; .s, 

 nervous system ; ot, oto- 

 cyst ; ph, pharynx ; st, 

 stomach. (After Kowalew- 

 sky.) 



Genus Fiona, Hancock and Embleton. FAMILY 8. PLEUROPHYLLIDIDAE, 

 Adams. Anterior tentacles in the form of a digging shield ; mantle 

 naked ; tegumentary papillae or " branch i " situated along the sides of 

 the foot, beneath the mantle border. Genus Pleurophyllidia, Meckel 

 (Fig. 167). FAMILY 9. DERMATOBRANCHIDAE, Fischer. Like Pleuro- 



