123 



GRYPH^A. 



5l 



Sowerbys Genera, No. 6, pi. 5. 



This genus, called by Lamarck Gryphaea, has hitherto 

 been considered by other authors an Ostrea, to which 

 in fact it bears a great resemblance; but the peculiar 

 character of the lower valve, which is very deep and 

 carinated, its summit terminated in a long spirally re- 

 curved beak, slightly turned to one side, the edge sharp 

 and angular, and the circumstance of its never being 

 attached to other bodies, or, if it is, only at one small 

 point, clearly distinguishes it from that genus. Shell 

 inequivalve, the lower valve large, concave, carinated, 

 terminating in a spirally recurved beak; upper valve 

 small and flat, fitting into the lower one at a small depth 

 from the marginal edge. Hinge without teeth, a car- 

 dinal cavity arched and oblong, one muscular impres- 

 sion only on each valve. Recent specimens are rare, 

 and only one species is at present known. In a fos- 

 sil state there are many described, and their locali- 

 ties seem to indicate that this shell inhabits the sea 

 at a great depth. Sowerby has reunited this genus 

 to that of the Ostrea, pointing out strong grounds of 



