113 



Unio gIjAns Lea. 



Trans. Am. Philos. Soc, Vol. iv, p. 82, Fl. viii, Fig. 12, 1830; Observa- 

 tions on the Gennn Unio, Vol. i, \>. 92, PI. viii, Fig. 12. Ohio Eiver (PI. iii, 

 Figs. 14-l(i). 



Unio pnllus (Jonvdd. Monography Family Uaionidir, pp. 100, 101, Pl.lv, 

 Fig. 2, 1830. Waleree River, South Carolina (PI. v, Figs. 32-34). 



Unio f/ranutaius hea,. Proc Acad. Nat. Soi. Piiila , Vol. xiii, p. 60, 1861; 

 Jour, Acad. Nat. Sci. Phila., Vol. vi, \k 48, PI. xvi, Fig. 46, 1866; Observa- 

 tions on the Gevns J^nio, Vol. xl, p. o2, PI. xvi, f^ig 40. Big Prairie Creek, 

 Alabama (PI. iv, Figs. 23-2-5). 



Unio fjermanus Lea. I'roc. Acad. Nat. Sci. Phila., Vol. xiii, p. 40, 1861; 

 Jour. Acad. Nat. Sci. Philn., Vol. vi, p. 4H, PI. xix, Fig. o4, 1866; Observa- 

 tions on the Genus Unio. Vol. xi, }>. 5;!, PI. xix, Fig. 54. Coosa River, Ala- 

 bama (PI. iv. Figs. 26-28). 



Unio cromweUii Lea. Proc. Acad. Nat. Sci. Phila., Vol. xvii, p. 89, 1865; 

 .Tour. Acad. Nat. Sci. Phila., Vol. vi, p. 25S, PI. xxxi. Fig. 73, 1868; Obser- 

 vations on the Gewm Umo, Vol. xii, p. 18, PI. xxxi, P'ig. 73. Kiokee Creek, 

 Albany, Georgia (PI. iv. Figs. 29-31). 



Unio ci/liiidrellux Lea. Jour. Acad. Nat. Sci. Phila., Vol. vi, p. 308, PI. 

 xlviii, Fig. 121, 1868; Observations on the Genus Unio, Vol. xii, p. 68, PI. 

 • xlviii. Fig. 121. East Tennessee, North Georgia, North Alabama (PI. iii, 

 Figs. 17-19). 



Unio corvunciilus Lea. Jour. Acad. Nat. Sci. Phila., Vol. vi, p. 314, PI. 1, 

 Fig. 127, 1868; Observations on the GotUf^ Unio, Vol. xii, [>. 74, PI. 1, Fig. 127. 

 Swamp Creek, Whitfield County, (ieorgia i PI. iii. Figs. 20-22). 



The t'ollowing conchologic description is based upon material taken in the 

 White River, Indiana, where the species attains its maximum development, both 

 in point of size and abundance. 



5/te// small, elliptical, striate, rather thick and snbangulate i)osteriorly, much 

 thicker anteriorly and rounded ; umbonea elevated, coarsely undulate, with irreg- 

 ularly crescent-shaped folds, three or four in niiiubcr; epidermis ratherthick, 

 dark greenish, obscurely radiate over the antericir [)ortion of the disk, a character 

 best seen by transmitted light, somewhat polished over the umbonal slope and 

 generally glos-y, lighter colored on the umbones; posterior margin sulcate in the 

 female, dorsal portion produced ; /('//a/new/ small, horn-c(dored, thin; both cardinal 

 and posterior hinge teeth double in the left and single in the right valve, the car- 

 dinals short, thick, heavy, serrate ; hitrra/s rather loug, striate, straight, lamellar ; 



