UNIVALVE MOLLUSC A. 



441 



with a well-developed mantle, furnished on the inside with a band of 

 tentacular filaments ; it is able to fold itself over its shell in such a 



Fig. 252. — Cypraea tigris (Linn.). 



Figs. 253 and 254. — Cyprsea argus (Linn.). 



manner as to envelop it all round. The head is provided with two 

 very long conical tentacles, each having a very large eye. The foot 

 is oval, elongate, and without operculum, and is well represented in 



