638 UNIO 
ber of faint, green rays that partly coalesce. The other incas- 
urements are from a shell which approaches more nearly to 
U. lehmanii. 
UNIO CHIPOLAENSIS Walker. 
“Shell ovate, not very thick, somewhat inflated in the um- 
bonal region, evenly rounded before and biangulate behind 
with a slight emargination just above the superior posterior 
angle; dorsal margin decidedly curved; basal margin slightly 
but regularly curved; epidermis smooth, chestnut-colored, 
darkening to black on the umbones, with several darker lines 
indicating arrested periods of growth. Umbonal slope well 
rounded towards the beaks, but flattening out and becoming 
slightly biangulate posteriorly. Beaks prominent, apparently 
incurved when perfect. Cardinal teeth compressed, crenulate ; 
those in the left valve are nearly in a straight line. Lateral 
teeth rather long, slender and slightly curved. Cicatrices dis- 
tinct. Cavity of the beaks large and rounded. Nacre salmon- 
color, darker anteriorly. 
Length 56.5, height 32, diam. 22 mm.” (Walker). 
Type locality, Chipola River, Fla. 
Unio chipolaensis WALKER, Naut., XVIII, 1905, p. 135, pl. 1x. 
HES AOsK7. 
“This species is a member of the group of U. buckleyi and 
is distinguished by the smooth, chestnut epidermis, entirely 
without rays, but ornamented with concentric dark bands 
such as occur in Pleurobema chattanoogaensis, inflated um- 
bonal slope and biangulated posterior extremity with a slight 
emargination above. It is related to some forms of U. burtch- 
ianus B. H. Wr., but differs in being less elongated and more 
inflated with more prominent beaks. The color both of the 
epidermis and nacre is also quite different.” 
UNIO CONFERTUS Lea. 
Shell usually more or less rhomboid, though sometimes 
nearly elliptical or slightly obovate, subsolid to solid, subin- 
flated to inflated, inequilateral; beaks moderately full and high, 
