m 



with a greenish epidermis, beneath which the surface 

 is of a milk white, highly polished, with from two to 

 four violet rays, diverging from the apex to the margin, 

 which is slightly tinged with violet. 



Sowerby has very properly changed the name of this 

 genus to that of Potamophila, Galathea being the name 

 given by Fabricius, (and adopted by La Marck,) to a 

 genus of Crustacea. 



Only one species is at present known. A beauti- 

 ful example of this rare shell is in the Tankerville 

 Collection; and the Provost of Eton has also a very 

 fine specimen. 



Galathea radiata. 



CYPKlNA. 



YENUS ISLANDICA. LinnCBUS. 



Pennant, pl> 53, f. 47. 

 The Cyprinae are in general of a large size, much 

 resembling the Veneres, but are distinguished from 

 them by having one impressed lateral tooth on the 

 front side, sometimes obsolete; the Nympha? or eallo- 



