GO NEW TJNIONIDzE OF THE UNITED STATES. 



Shell smooth, elliptical, rather compressed, very inequilateral, angular behind: 

 valves somewhat thin, thicker before; beaks slightly prominent ; epidermis yellowish- 

 brown, very much rayed and very shining; cardinal teeth small, compressed, erect 

 and crenulate; lateral teeth long, lamellar and straight; nacre white or salmon 

 colored and very iridescent. 



Proc. Acad. Nat. Sci. 1857, p. 85. 



Hal. — Catawba Kiver, Gaston Co., N. C. ; C. M. Wheatley and Dr. Genth. Deep 

 River, Gulf, N. C. ; Prof. Emmons. 



My cabinet and cabinets of Mr. Wheatley, Dr. Genth and Prof. Emmons. 

 Diam. -5, Length -9, Breadth 1-7 inch. 



Shell smooth, elliptical, rather compressed, very inequilateral, angular behind and 

 regularly rounded before; substance of the shell somewhat thin, thicker before; beaks 

 slightly prominent ; ligament short and light brown ; epidermis yellowish-brown, very 

 much rayed and very shining, with rather distant marks of growth ; umbonial slope 

 raised and angular; posterior slope rather wide, slightly raised, and furnished with 

 rays from the beaks to the margin ; cardinal teeth small, compressed, erect, crenulate 

 and double in both valves ; lateral teeth long, lamellar and straight ; anterior cica- 

 trices distinct, rather small and moderately impressed; posterior cicatrices confluent, 

 rather small and very slightly impressed ; dorsal cicatrices small and placed above the 

 cavity of the beaks ; cavity of the shell rather shallow and somewhat wide ; cavity 

 of the beaks small and subangular ; nacre white or salmon color and very iridescent. 



Remarks. — This is a brilliant little species with numerous small green rays. It is 

 near to lanceolatus, (nobis,) but is not so transverse nor so thin. The color of the 

 epidermis is also of a darker yellow, and is covered usually with green rays. 



Ui\io Neusensis. PI. 4, fig. 208. 



Testa laevi, oblongi, subcompressa, ad latere planulata, postice tumida et biangulata, valde irjEequilaterali ; 

 valvulis subcrassis; natibus prominulis; epiderrnide mgricante, striata et eradiata; dentibus cardi- 

 nalibus parviusculis, crenulatis, in utroque valvule- subduplieibus; lateralibus piselongis subcurvisque ; 

 margarita vel purpurea vel salmonis colore tincta et iridescente. 



Shell smooth, oblong, subcompressed, flattened at the side, swollen and biangular 

 behind, very inequilateral ; valves rather thick; beaks prominent; epidermis blackish, 

 striate and without rays; cardinal teeth rather small, crenulate and somewhat double 

 in both valves; lateral teeth very long and somewhat curved; nacre purple or salmon 

 color and iridescent. 



Proc. Acad. Nat. Sci. 1858, p. 41. 



Hal. — Neuse River, six miles from Raleigh, N. C. Prof. Emmons. 



My cabinet and cabinet of Prof. Emmons. 

 Diam. -6, Length 1-2, Breadth 2-6 inches. 



