II. MOLLUSCA. 



Body without articulations ; furnished with 

 head and eyes ; and never inclosed in a bi- 

 valve shell. 



a. Limacida^. 



Animal terrestrial. Body elongated, furnished with 

 an external or internal shell. 



5. LiMACELLUS. Shell internal, oval, flat, without 

 visible spire. 



Type. Limacella Parma, Brard. p. 110. 



6. Testacellus. Shell external, oval, concave, spi- 

 ral at the tip, covering the lower extremity of the 

 animal. 



Type. Testacellus Maugei, Sowerby, Genera. 



b. Helicidce. 

 Animal mostly terrestrial, furnished with four more 

 or less cylindrical tentacula. Shell with or without 



