DESCRIPTION OP FIFTY-TWO SPECIES OF UNIONID^. 



Unio subglobatus. pi. 1, fig. 3. 



Testa Isevi, suborbiculata, valde inflata, iiiEequilaterali; valvulis per crassis ; natibus turaidis, elevatis, 

 incurvis; epidermide tenebroso-fiisca, ad apicem maculata et radiata; dentibus eardinalibus par- 

 viusculis, compressis suleatisque ; lateralibus crassis, curvatis corrugatisque ; margarita argentea 

 et iridescente. 



Shell smooth, suborbicular, very much inflated, inequilateral; valves very thick; 

 beaks swollen, elevated, incurved ; epidermis dark brown, spotted and radiate 

 towards the tips ; cardinal teeth rather small, compressed and sulcate ; lateral 

 teeth thick, curved and corrugate ; nacre silver white and iridescent. 

 Proc. Acad. Nat. Sci., 1871, p. 191. 



Hah. — Florence, Ala., B. Pybas; Nashville, Tenn,, Pres. J. B. Lindsley. 



My cabinet. 

 Diam. 1-3, Length 1-6, Breadth 1-8 inch. 



Shell smooth, orbicular, very much inflated, inequilateral ; substance of the 

 shell very thick, thicker before ; beaks very much inflated, very prominent and 

 incurved; ligament short, thick and dark brown; epidermis dark brown, maculate, 

 rayed towards the beaks, and with rather close marks of growth ; urabonial slope 

 raised and rounded ; posterior slope widely cordate and without rays ; cardinal 

 teeth rather small, deeply lobed, compressed, corrugate, and disposed to be treble 

 in the left valve ; lateral teeth thick, curved, abrupt at the end and corrugate ; 

 anterior cicatrices distinct, small and deeply impressed ; posterior cicatrices dis- 

 tinct, rather small, and well impressed ; dorsal cicatrices within the cavity of the 

 shell and under the plate, which is very large ; cavity of the shell rather deep and 

 rounded ; cavity of the beaks very shallow and rounded ; nacre silver white and 

 iridescent. 



Remarks. — This is the most globose species with which I am acquainted except 

 capax. Green, which is a very large and very diff'erent species. They cannot be at 

 all compared except in the single character of globosity. I have three specimens 

 before me, all of different ages. The oldest is much eroded at the beaks and 

 umbones, and presents only a few maculations along the umbonial slope. The 

 middle aged and young one have maculated rays and are slightly polished towards 

 the tips. In outline it is allied to ehenus, suhrotiindus, and pilaris (nobis). It is 

 more inflated than either. It is not so retuse in the beaks as ehenus, nor has it so 

 dark an epidermis. It is a smaller species than suhrotundus, and more inflated. 

 It diff"ers from pilaris in having a lighter epidermis, and in being more rotund. 

 Neither of the specimens have beaks perfect enough to present undulations at the 

 lips. 



