98 



GASTROPODA. 



Family I. ELYsiADiE. 



Without mantle or breatHng organs ; body 

 covered witli cilia ; a single row of tongiie-teetli ; 

 eyes sessile, on the sides of the head ; tentacles 

 simple or wanting. 



Elysia (Risso). Slug-like, flattened, with lateral 

 expansions ; tentacles simple, in front of the eyes ; 

 foot narrow. 



E. viridis. Fig. 127 ; n.s. 



e 



\J 



127 



128 



129 



130 



Actceoma (Quatref.). Head large, distinct, crested 

 at the sides, the crests prolonged behind into two 

 short tentacles, behind which are the eyes ; vent in 

 the middle of the back. 



A. corrugata. Fig, 128 ; rna^. 



Cenia (Alder and Hancock). Head slightly 

 angled, carrying two slender tentacles on its back ; 

 eyes behind and outside them ; back elevated. 



C. Cocksii. Fig. 129 ; mag. 



Lima])ontia ( Johnst.) . Leech-like, low in front, 

 rounded and elevated behind ; head distinct, with 



