MOLLUSCA OR UNIVALVES. 203 



These shells are found on the shores of the 

 Indian Ocean and Senegal; and one species, 

 Tornatella fasciata, inhabits our own coasts. 

 They form an operculum. 



69. Melampus (Montford). — Shell small, 

 conical; spire depressed; pillar or 

 inner lip having one or two plaits, 

 outer lip thickened inside ; no oper- 

 culum. Animal having two ten- 

 tacula, with eyes at the base. — 

 Species doubtful. 



This genus inhabits the shallow parts of the 

 coast of the West Indian Isles, where it is 

 found creeping on the mangrove roots. It is 

 perfectly amphibious, and very tenacious of 

 life. 



70. Pyramidella. — Shell tur- 

 reted; pillar having three plaits; 

 outer lip thin ; no epidermis. Ani- 

 mal not known. — There are 1 1 

 species recent, and 8 fossil. 



This group of shells is found in 

 the Indian and American seas. 



