FRESHWATER AND LAND SHELLS. 29 



thin ; beaks somewhat prominent ; epidermis brown ; cardinal teeth compressed ; lateral 

 teeth long and straight ; nacre purple. 



Hab. Florida. J. C. Jay, M.D. 



My Cabinet. 

 Diam. '8, Length 1-2, Breadth 2'5 inches. 



^Shell narrow-elliptical, transverse, very inequilateral, subangular 

 behind; subcarinate; substance of the shell thin; beaks somewhat 

 prominent ; ligament rather long ; epidermis brown, and apparently 

 without rays ; cardinal teeth compressed, in the left valve deeply cleft 

 and elevated; lateral teeth long and straight; anterior cicatrices dis- 

 tinct ; posterior cicatrices confluent ; dorsal cicatrices situated in the 

 centre of the cavity of the beaks ; cavity of the shell small ; cavity of 

 the beaks small ; nacre purple and iridescent. 



Remarks. — Among other shells for which I am indebted to Dr Jay, 

 were single opposed valves of two individuals of nearly the same size, 

 and for which I propose the name of Jayensis. I do not know from 

 what part of Florida they came. This species strongly resembles the 

 nasutus (Say), but is not quite so transverse a shell, approaching the 

 complanatus. The nacre of both the individuals is of a light purple, 

 bordering on a pinkish tint. In young specimens, it may perhaps be 

 found to possess rays. 



Unio hopetonensis. Plate IX. fig. 24. 



Testa suboblonga, transversa, incequilaterali, compressa, postich biangidata, ad laius 

 planulala; valvulis subcrassis; natibus prominulis, ad apices undulatis ; epidermide tenebroso- 

 fused; dentibus cardinalibus parvis; laleralibus longis curvisque; margarita purpiireA et 

 iridescente. 



Shell somewhat oblong, transverse, inequilateral, compressed, biangular behind, flat- 

 tened at the sides; valves somewhat thick; beaks scarcely prominent, undulated at the 

 tip ; epidermis dark brown ; cardinal teeth small; lateral teeth long and curved ; nacre 

 purple and iridescent. 



Hab. Hopeton, near Darien. Professor Shepard. 



YI. H 



