672 UNIO 
UNIo PLANTII Lea. 
Shell nearly elliptical or a little obovate, compressed, sub- 
solid, inequilateral ; beaks apparently low and compressed, their 
sculpture not seen; posterior ridge low, ending behind just 
below the median line; anterior end a very little narrowed, 
rounded; posterior end feebly subtruncated above, rounded 
below; basal and dorsal line curved; surface with irregular, 
concentric sulcations; epidermis greenish-brown, subshining ; 
pseudocardinals small, roughened, double in each valve, the 
upper in the right valve small; laterals remote; muscle scars 
impressed; nacre lurid purplish, iridescent behind; pallial line 
crenate. 
Length 93, height 56, diam. 26 mm. 
Type locality, Flint River; near Macon, Georgia. 
Unio plantu Lea, Pr. Ac. N. Sci. Phila., IX, 1857, p. 171; Jl. 
Ac. N. Sci? Phila... V5 1859, 2-102; pl ext, fies Zon @ass 
VII, 1859, p. 10, pl. xx1, fig. 76—Sowerrsy, Conch. Icon., 
XVI, 1868, pl. Lxxxvil, fig. 473.—SIMPSON, Syn., 1900, p. 
729. = 
Margaron (Unio) plantii Lea, Syn., 1870, p. 43. 
The only shell seen, the type, appears to be a little injured 
behind. It is a peculiar disk-like form, nearly evenly elliptical, 
the least trifle rhomboid, and unevenly sulcate. 
UNIo stRUMOSUS Lea. 
Shell subrhomboid, rather short, slightly inequilateral, sub- 
solid, scarcely inflated; beaks apparently neither full nor high ; 
posterior ridge full, narrowly rounded, ending behind in a 
blunt point at or near the base; surface with uneven growth 
lines; epidermis dirty yellowish-brown or greenish-brown, sub- 
shining ; pseudocardinals rather strong, ragged, double in the 
left valve and single in the right, laterals short, heavy, much 
curved; dorsal cavities compressed; muscle scars well marked : 
nacre dirty, lurid whitish. 
Length 68, height 45, diam. 24 mm. 
Type locality, Yadkin River, North Carolina. 
