NEW UNIONIDvE OF THE UNITED STATES. 59 



Unio spadiceus. pi. 1, fij?. 201. 



Tistrilrevijclliptica, subcompressa, inajquilatcralijpostice subbiangulata, subemarginata; valvulis subtcnuibua, 

 anticc crassioribus; natibus vix prominulis; epidermide spadicea, eradiala; dentibus cardiDalibus 

 parvis crenulatisque ; lateralibus sublongiu subrectisque ; margaritri salmonis colore tiocta ct iridescentc. 



Shell smooth, elliptical, somewhat compressed, inequilateral, subbiangiilar behind, 

 subemarginate ; valves rather thin, thicker before; beaks scarcely prominent; epider- 

 mis reddish brown, without rays ; cardinal teeth small and crenulate ; lateral teeth 

 rather long and nearly straight; nacre salmon color and iridescent. 

 I'roc. Acad. Nat. Sci. 1857, p. 86. 



Ilah. — Deep River, Gulf, N. C, Prof. Emmons ; and mountain streams, N. C, Mr. 

 Joseph Clark. 



My cabinet, and caljinets of Prof Emmons and Mr. Clark. 

 Diam. -4, Length -7, Breadth 1-5 inch. 



Shell smooth, elliptical, somewhat compressed, inequilateral, subbiangular behind, 

 subemarginate at base ; substance of the shell rather thin, thicker before ; beaks 

 scarcely prominent ; ligament short, thin and light brown ; epidermis reddish brown, 

 without rays; umbonial slope slightly raised and obtusely angular; posterior sloi^e 

 rather narrow, raised into a carina; cardinal teeth small, crenulate and double in 

 both valves; lateral teeth rather long and nearly straight; anterior cicatrices distinct, 

 small and well impressed; posterior cicatrices confluent, rather small and slightly 

 impressed ; dorsal cicatrices placed across the cavity of the beaks ; cavity of the 

 shell shallow and wide ; cavity of the beaks very shallow, scarcely observable ; nacre 

 salmon color and iridescent. 



Remarlcs. — I have only two specimens before me. The one figured is from my 

 friend the late Joseph Clark, to whom I am indebted. for so many species and so much 

 information in this our favorite branch of zoology. The siwcimen is apparently 

 an adult. The exact habitat is not known. A half-grown one is from Prof 

 Emmons, and was taken in Deep River, N. C. In general character it is near to 

 fuhus, (nobis,) and reminds one of lanceolahis, (nobis,) but may easily be distin- 

 guished from both. 



Unio striatulus. PI. 2, fig. 202. 



Testa lievi, triangular!, subinflafa, subrequilaterali, postice angulata; valvulis subcrassis, antieo erassioribus; 

 natibus elevatis, acuminatis, ad apices rugoso-undulatis; epidermide castanea, minute striata, obsolete 

 radiata; dentibus cardinalibus parvulis. subcompressis, in utrcque valvulo duplicibus crenulatisque; 

 lateralibus brevibus, subcrassis rectisque ; margarita vel alba vel crocea et iridescente. 



Shell smooth, triangular, somewhat inflated, nearly equilateral, angular behind ; 

 valves rather thick, thicker before ; beaks elevated, acuminate, rugosely undulate at 

 the tips; epidermis chestnut brown, minutely striate, obscurely radiate; cardinal 



