222 Notes on Species of Corbiculadce. 



siderably bent towards the end in the neighborhood of the 

 adductor muscle. 



Comparing this species with Corb. striatella from the same 

 locality, we find it to be more solid, transversely less rounded, 

 and less inflated ; the beaks are less swelled and the posterior 

 margin is more abrupt ; the hinge is broader and more solid, 

 and the color of the interior of the valves is lighter and not so 

 highly polished. 



Fig. 54. 



40. Corbicula StiBiipsoniana, now spec 



C. testa trigona, obliqua, subsequilaterali, inflata ; latere antico rotun- 

 dato, postico longiore, obtuso ; umbouibus 

 magnis, tumidis, approximates, incurvis ; valvis 

 solidis, intus candidis, ad margines violaceis ; 

 epidermide castanea subnitente vestita ; sulci's 

 regularibus distantibns ; cardine incrassato ; 

 lunula inconspicua, ovatolanceolata. 



Long. 34 ; lat. 25 ; diam. 17 mill. 

 Hab.— ? Coll. Prime. 



Corbicula Stimpsoniana. m , . .. . . . ... 



Ihe shell is trigonal, oblique, some- 

 what equilateral and inflated. The anterior side is rounded, 

 the posterior is longer and is obtuse. The beaks are large and 

 are considerably protruded, they are approximate at apex and 

 curve inwardly. The valves are solid. The interior is white 

 with a circle of dark violet extending round the margin of 

 the shell, with the exception only of the portion taken up by 

 the cardinal teeth, which are white. The epidermis is of a 

 chestnut color and is slightly polished. The strise are regular, 

 distant, much raised, and sharp. The hinge is broad and strong. 

 The lunula is indistinct, in shape it is oval. 



The Corb. Stimpsonia?ia seems to be a well characterized 

 species, and not to possess any very close affinities with any of 

 its congeners. I have no positive knowledge as to the country 



