NEW UNlONirU-: OF THE UNITED STATES. 99 



Unio Ocmulgeexsis. pi. 14, fig. 243. 



Testa loBvi, transversa, inflatri, postice obtusi; biangulata, antict- subtruncata, valdo inxtjuilatcrali ; valvulis 

 crassis, anticc crassioribus ; natlbus prominulis; epidermiiJe tenebroso-fusca, eradiata, superoe micanti, 

 inferoe valdO striata; dentibus cardinalibus parviusculis, pjramidatis striaiisque; lateralibns prselongis, 

 laniellatis subrectisque ; margarita aurantiii et vald6 iridescente. 



Shell smooth, transverse, inflated, obtusely biangular behind, somewhat truncate 

 before, very inequilateral ; valves thick, thicker before ; beaks a little prominent ; 

 epidermis dark brown, eradiate, shining above and much striated below; cardinal 

 teeth rather small, pyramidal and striate ; lateral teeth very long, lamellar and 

 nearly straight ; nacre golden and very iridescent. 

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



Ilab. — Little Ocmulgee River, Lumber City, Georgia. S. W. Wilson, M. D. 



My cabinet and cabinet of Dr. Wilson. 

 Diam. 1-3, Length 2, Breadth 4 1 inches. 



Shell smooth, transverse, inflated, obtusely biangular behind, subtruncate before 

 and very inequilateral; substance of the shell thick, thicker before; beaks a little 

 prominent, nearly terminal ; ligament long, rather thick and dark brown ; epidermis 

 dark brown, without rays, shining above, with loose, scaly strise near the margin, 

 and with irregular, indistinct marks of growth ; umbonial slope slightly raised and 

 very obtusely angular ; posterior slope long, elliptical and slightly furrowed ; cardinal 

 teeth rather small, pyramidal, striate and crenulate ; lateral teeth very long, lamellar 

 and nearly straight ; anterior cicatrices distinct, very large, corrugate and deeply im- 

 pressed ; posterior cicatrices confluent, very large and well impressed ; dorsal cicatrices 

 placed a little above the centre of the cavity of the beaks ; cavity of the shell not deep, 

 but wide ; cavity of the beaks very shallow and rounded ; nacre golden, inclining to 

 salmon, very rich and iridescent. 



Remarhs. — A single specimen, and without the soft parts, was received from Dr. 

 Wilson. The beaks are much eroded, and do not, of course, give the character of the 

 undulations. It is a well marked species, with a nacre, which yields to no other 

 species in richness, being very satin-like, pure and perfectly iridescent. Younger and 

 more perfect specimens may exhibit obscure rays; this one has none whatever. Li 

 outline, it is nearest to verutus (nobis), but it is a larger species, with a much darker 

 epidermis, is more inflated, the verutus being flattened on the sides. 



Unio rubious. PI. 14, fig. 244. 



Testa sulcata, stibtriangulari, valde inflata, ad latere planulata, subaequilaterali ; valvulis subcrassis, antied 

 crassioribus ; natibus subprominentibus, subinflatis ; epidermide tenebroso-rufo-fusca, eradiata, superne 

 micanti, infcrne striata; dentibus cardinalibus crassiusculis, elevatis, subpjramidatis crcnulatisque ; 

 latcralibus sublongis, curvis subcrassisque; margarita vel rosacea vel alba vel salinonis colore tinctA 

 et iridescente. 



