M NEW UNIONID^ OF THE UNITED STATES. 



and it is more inflated also. It reminds one of mix (nobis), but it is a larger species, 

 with beaks more terminal, but not so much elevated. The color of the epidermis, 

 which is rather unusual, being of a dark olive, is remarkably uniform ; neither of these 

 specimens have rays. The beaks are not perfect enough to exhibit any undulations 

 at the tips. It was supposed that this was the perovatus of Mr. Conrad, but it cannot 

 be the same species described and figured by him, under that name, in the "American 

 Journal of Science," vol. 28, pi. 1, fig. 3. Neither the description nor figure answers 

 to concolor, and the marks of growth in his figures are fifteen, while this species has 

 five or six only. 



Unio fabaceus. PL 13, fig. 238. 



Testa laevi, oblonga, subquaJrata, subinflata, postice subbiangulata, subasquilaterali ; valvulis crassiusculis, 

 antico crassioribus; natibus prominulis; epidermide tenebroso-fusca, micanti, obsolete radiata; denti- 

 bus cardinalibus parvis, erectis, acuminatis, crenulatis ; lateralibus curtis, lamellatis subcurvisque ; 

 margarita purpurescenti, salmonis colore tincta et valde iriSescente. 



Shell smooth, oblong, subquadrate, rather inflated, subbiangular behind, nearly 

 equilateral; valves somewhat thick, thicker before; beaks slightly jarominent; epi- 

 dermis dark brown, shining, obscurely radiate ; cardinal teeth small, erect, pointed, 

 crenulate ; lateral teeth short, lamellar and somewhat curved ; nacre purplish and 

 salmon color and very iridescent. 



Proc. Acad. Nat. Sci. 1861, p. 38. 



Eah. — Oostanaula River, Georgia. Bishop Ellliott. 



My cabinet and cabinet of Bishop Elliott. 

 Diam. -6, Length, -9, Breadth, 1-3 inch. 



Shell smooth, oblong, subquadrate, rather inflated, subbiangular behind and nearly 

 equilateral ; substance of the shell somewhat thick, thicker before ; beaks slightly 

 prominent ; ligament very short, thin and light brown ; epidermis dark brown, inclin- 

 ing to olive, shining, very obscurely rayed, with distant, well marked lines of growth ; 

 umbonial slope inflated and rounded ; postesior slope rather broad, with a small carina, 

 with a rather broad furrow, which causes an emargination at the edges ; cardinal teeth 

 small, erect, acuminate and crenulate ; lateral teeth short, lamellar and somewhat 

 • curved ; anterior cicatrices distinct, rather large and well impressed ; posterior cica- 

 trices confluent, large and slightly impressed ; dorsal cicatrices placed within the 

 cavity of the beaks at the base of the cardinal teeth ; cavity of the shell rather deep 

 and rounded ; cavity of the beaks somewhat deep and angular ; nacre purplish and 

 salmon color and very iridescent. 



Remarks. — A single specimen only of this little species was received from Bishop 

 Elliott, and without the soft parts. In outline it is near to cacao (nobis), and is about 

 the same size, but cannot be confounded with that species, as it is a thinner shell, 

 more inflated, has not the flattened sides, and is not so dark in the epidermis. It is 



