298 NEW UNIONID^, MELANID^, ETC., 



epidermis reddish-brown or yellowish, shining, radiated, with very distant lines of 

 growth; umbonial slope low and slightly angular; posterior slope very narrow 

 elliptical and raised into a sharp carina, made dark green with rays ; cardinal teeth 

 thick, sulcate and slightly crenulate ; lateral teeth long, thick, lamellar and nearly 

 straight; anterior cicatrices distinct, large and well impressed; posterior cicatrices 

 confluent, large and slightly impressed ; dorsal cicatrices placed above the centre of 

 the cavity of the beaks; cavity of the shell very shallow and wide; cavity of the 

 beaks very shallow and obtusely angular ; nacre white or purple and very iridescent. 

 Remarks. — Among the Unionidce procured by Mr. Wheatley from North Carolina 

 were several of this species, which belongs to the complanatus group. It is allied to 

 humerosus, herein described, but is a thicker shell and a little more transverse. The 

 specimen from Carter's Creek, Geo., has a white nacre and may possibly be a different 

 species. The older specimens are dark, reddish-brown and some are without rays. 

 The younger and more perfect specimens are yellowish, and the one figured is covered 

 with fine rays. 



Unio nubilus. pi. 44, fig. 110. 



Testa Isevi, oblonga, snbcompressa, insequilaterali, postice biangulari, antice rotundata; valvulis crassis, 

 antice crassioribus ; natibus prominulis ; epidermide tenebroso-fusca, eradiata ; dentibus cardinali- 

 bus crassis, sulcatis corrugatisque ; lateralibus crassis, lougis, corrugatis lamellatisque ; margarita 

 nubila, salmouea et purpurea, iridescente. 



Shell smooth, oblong, subcompressed, inequilateral, biangular behind and rounded 

 before; valves thick, thicker before ; beaks a little prominent; epidermis dark brown, 

 eradiate ; cardinal teeth thick, sulcate and corrugate ; lateral teeth thick, long, 

 corrugate and lamellar ; nacre cloudy, salmon colored and purple, iridescent. 

 Proc. Acad. Nat. Sci. 1868, p. 161. 



Eah.—Yavf Creek, Mecklenburg Co., N. C, C. M. Wheatley. 

 Diam. -Q,' Length 1-8, Breadth 3-2 inches. 



Shell smooth, oblong, subcompressed, inequilateral, biangular behind and rounded 

 before; substance of the shell thick, thicker before; beaks a little prominent; liga- 

 ment long, thick and very dark brown ; epidermis very dark brown, without rays 

 and with rather close lines of growth ; umbonial slope somewhat raised and obtusely 

 angular; posterior slope narrow elliptical, somewhat raised, with rather a wide 

 furrow on each valve from the beaks to the posterior margin; cardinal teeth thick, 

 sulcate and corrugate; lateral teeth thick, long, corrugate and lamellar; anterior 

 cicatrices distinct, very large and well impressed ; posterior cicatrices confluent, 

 large and slightly impressed ; dorsal cicatrices placed over the centre of the cavity 

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

 shallow and obtusely angular; nacre cloudy, salmon-color and purple, iridescent. 



