186 POPULAR CONCHOLOGY. 



Family 3. — Melanidce* 



The Melanidce are all fluviatile shells, mostly 

 exotic, and covered by a black or greenish 

 brown epidermis. The right lip is always 

 sharp, and the lips disunited. The animal has 

 two tentacula and an operculum, and breathes 

 only water. There are two genera. 



53. Melania. — Shell oblong, often turreted, 

 exterior wrinkled, and the 

 whorls sometimes surmount- 

 ed with spires or knobs; 

 aperture pear-shaped; oper- 

 culum horny ; almost all have 

 a brown or black epidermis. 

 Animal having two tentacula, 

 with eyes at the base ; foot generally short and 

 thick. — 36 species recent, 7 fossil. 



Found in a great many parts of the world ; 

 abundant in Asia, but rare in Europe f, ex- 

 cept in a fossil state. They inhabit rivers. 



* Les Melaniens, Lamarck. 



f M. helvetica is found in fresh waters in Switzerland 

 and Italy. 



