ASTARTE.— Plate III. 



round ; posterior side angular, compressed in front 

 of the angle, dorsal margin much sloped. 



SOWERBY. 



Hab. Northern Seas. 



This shell is so decidedly different in form from the 

 normal specimens of Astartc arctica, that it seems desir- 

 able to separate it. 



Species 21. (Fig. a, l>, Mus. Brit.) 



AsTAKTE ARCTICA. Asf. testA elUptico-suhorhicuJari, 



subconipressd, prope umbones medioque subtiregu- 



lariter liratd, versHs marginem Icevigatd ; latere 



autico hrevissimo ; latere postico obscure angulato, 



truncato ; margine dorsali declivi ; margine ventrali 

 rotunda, intiis loevigato. 



The Arctic Astarte. Shell elliptical-suborbicular, 

 subcompressed, rather irregularly ridged near the 

 umboes and at the middle, smooth towards the 

 margin ; anterior side very short ; posterior side 

 obscurely angular, truncated ; dorsal margin 

 sloped ; ventral margin rounded, smooth within. 



Gray (Crassina). App. Capt. Parry's Voyage. 



Vemis borealis, Chemnitz. 



Astarte ci/jirinoides, Duval. 



Crassina corrugata, Brown. 



Astarte Japonica, Jay ? 



Hab. Northern Seas. 



