676 UNIO 
faint biangulation between the median line and base; surface 
nearly smooth or with a few uneven growth lines; epidermis 
greenish-yellow to brownish, often feebly rayed; pseudo- 
cardinals delicate, subcompressed, double in each valve, the 
upper in the right valve feeble; laterals delicate, nearly 
straight ; muscle scars scarcely impressed ; nacre whitish to pale 
brownish-purple, iridescent behind. 
Length 74, height 35, diam. 22 mm. 
Length 72, height 35. diam. 17 mm. 
Type locality, Tobesaufke Creek, near Macon, Georgia. 
Unio paliatus RAVENEL, letter—Conrap, Pr. Ac. N. Sci. 
Philar, Vie 1853. pa2s4: 
Margarita (Umo) paliatus Lea. Syn., 1836, p. 31; 1838, p. 22. 
Margaron (Umio) pahatus Lea, Syn., 1852, p. 33; 1870, p. 53. 
Unio palliatus RAVENEL, Cat., 1875, p. 57. 
Umo .errans. Lea, Pr. Ac. N. Sci Phila. VIII, 1856, p. 2625 
Why Ac-N.? Sct. Phila. [Vj 2S58.0p) 60; plod wie ers Olne. 
VI, 1858, p. 60, pl. 1x, fig. 42.—SIMPSON, Syn., 1900, p. 730. 
Margaron (Unio) errans, LeA, Syn., 1870, p. 52. 
Unio vicinus Lea, Pr. Ac. N. Sci. Phila., WIII, 1856, p. 262; 
jl. Ac. N. Sci,- Phila, 1V., 1858; ‘p: 61, pk ax, hes; Obs. 
VI, 1858; p. 61, pl ix, fis. 43: 
Margaron (Umo) vicinus Lea, Syn., 1870, p. 52. 
A rather delicate, subrhomboid or sometimes subelliptical, 
compressed to convex, form with no striking characters. It 
is usually nearly smooth and shining. It is a much less robust 
shell than U. tuomeyi. 
Dr. Lea credits U. paliatius to Ravenel’s letter, (Syn., 1836), 
and Ravenel, (1875), ascribes it to Lea, but neither ever de- 
scribed it so far as I know. 
UNIO SAGITTIFORMIS Lea. 
Shell elongated, rhomboid, compressed, subsolid, inequilat- 
eral: beaks slightly elevated, but not inflated, their sculpture 
consisting of strong, longitudinal, somewhat corrugated ridges ; 
posterior ridge well developed, ending in a somewhat produced 
point near the base of the shell; dorsal slope very obliquely 
