UNIO 661 
An elongated, rhomboid, somewhat arcuate form with a 
high posterior ridge and almost shining epidermis. Many of 
the shells are almost sulcate. 
Unio TUOMEYI Lea. 
Shell somewhat elongated, solid, varying from subrhomboid 
to nearly elliptical, subcompressed to subinflated, inequilateral ; 
beaks scarcely elevated or inflated, their sculpture not seen; 
dorsal line curved ; basal line rarely incurved, generally straight 
or rounded; posterior ridge well developed, single and often 
angular above, often becoming feebly and narrowly double 
below, ending behind in a point or narrow biangulation below 
the median line; surface usually rather smooth; epidermis 
tawny to brownish, often more or less rayed, smooth and 
shining; left valve with two ragged pseudocardinals and two 
laterals ; right valve with one pseudocardinal, sometimes with 
a faint one above it, and one lateral; beak cavities shallow ; 
muscle scars impressed; nacre generally tinted purple. 
Length go, height 46, diam. 25 mm. 
Length 77, height 41, diam. 21 mm. 
North Carolina to Alabama. 
Type locality, Abbeville District, S. C. 
Unio tuomevi Lua, Tr. Am. Phil. Soc., X, 1852, p. 256, pl. X11, 
fig. 4; Obs., V, 1852, p. 12. pl. x11, fig. 4.—SimPson, Syn., 
1900, p. 726. 
Margaron (Unio) tuomeyi LEA, Syn., 1852, p. 33; 1870, Pp. 53. 
Unio barrattii Lea, Tr. Am. Phil. Soc., X, AS p: 256, pl. x11, 
feos Ops V 1852; sp. 12, pl: xi, hg. 5. 
Margaron (Unio) barrattii Lea, Syn.. 1852, p. 37; 1870, p. 245. 
Unio barrotti Ptrt., Conch. Sam., ILI, 1890, p. 145. 
Unio pullatis Lea, Pr. Ac. N. Sci. Phila., VIII, 1856, p. 262. 
Unio pullatus Lea, Jl. Ac. N. Sci. Phila., IV, 1858, p. 57, pl. 
vin, fig. 39; Obs., VI, 1858, p- 57, pl. vin, fig. 39.—KustEr, 
Conch. Cab. Unio, 1871, p. 247, pl. Lxxxtt1, fig. 3—SoweEr- 
By, Conch. Icon., XVI, 1868, pl. Lxvi, fig. 335. 
Margaron (Unio) pullatus Lea, Syn., 1870, p. 60. 
