196 POPULAR CONCHOLOGY. 



Family 6. — Janthinidce* 



This family consists only of one genus. 

 The shell is marine, and the animal breathes 

 water only. 



63. Janthika. — Shell round, whorls slightly 

 angulated; right lip 

 forming an angle at 

 the lower part of the 

 mouth with the co- 

 lumella, which is pro- 

 duced so as to meet 

 it ; very fragile, thin, 

 and of a purple colour. Animal, head furnished 

 with a round proboscis armed with little hooks ; 

 two tentacula with eyes at the base ; the under 

 surface of the foot furnished with a vesicular 

 or bubble-like apparatus, which prevents the 

 animal from crawling, but enables it to float on 

 the surface of the water with the shell down- 

 wards. — 2 species, recent. 



One species, J. fragilis, is found on our coasts 



* Les Janthines, Lamarck. 



