4/8 



MOLLUSKS I GASTEROPODS. 



contains gasteropods which have a shell with an expand- 

 ed lip deeply notched near the canal, and a claw-shaped 

 operculum. They feed on dead animals. Their shells 



Fig. 382. 



Pteroceras latnbis, L. One half. Chinese Seas.* 



Fig. 383- 



Fig. 384- 



S trombus pugilis, L. One half. 

 West Indies. 



Aforrhais occidentalism Beck. 

 New Ensrland. 



are extensively used in the manufacture of shell cameos. 

 The living species are estimated at about eighty, and 

 the fossil at two hundred. Marine. 



* Foreign shells are quite as likely to fall into the hands of American 

 students as those of our own coast. 



