UPPER TENNESSEE DRAINAGE. 591 
known from the Tennessee in North Alabama, but which has not 
yet been recorded from the upper Tennessee. T. turgidula agrees 
with the latter in the biangulate posterior ridge, but the biangulation 
is much less pronounced, and the depression or furrow in front of 
it is less developed. In the female (deviatus), the biangulation is 
also present, but indistinct, and the furrow is obliterated, being 
filled by the expansion of the shell. The female resembles, to a 
degree, that of T. florentina, but has the shell, as Simpson states, 
more elongated, and has fuller and higher beaks (the latter charac- 
ters hold also good for the male). 
This species has been recorded from Cumberland and Tennessee 
rivers (not recently found by Wilson & Clark, ’14, in Cumberland), 
and from Duck River, Tenn. (Call), but only one definite locality 
is known (Florence, Lauderdale Co., Ala.). Hinkley reports it from 
Shoals Creek, Lauderdale Co., Ala. The Carnegie Museum has it 
from Bear Creek, in Franklin Co., Ala. I have found it in the 
upper Tennessee drainage, where it is not rare in the Holston proper 
from Knox Co. up to Austin Mill, Hawkins Co., Tenn. I found it. 
also in Emory River, Harriman, Roane Co., Tenn. In the Walker 
coll. it is represented from the Holston, Rogersville, which is prac- 
tically the same locality as Austin Mill. 
Type locality: Cumberland River and Florence, Ala. 
86. TRUNCILLA FLORENTINA (Lea), 1857. 
Unio florentinus Lea, ’57—Truncilla florentina Simpson, ’14, p. 30 
(excl. turgidulus). 
This species has not a biangulate posterior ridge, but this ridge 
is rounded, and the radial depression in front of it is hardly de- 
veloped, indicated only by a flattening of the shell. In the female, 
the posterior expansion of the shell may become very large, and is 
generally of the color of the rest of the shell, or lighter, but not uni- 
formly dark green, as in 7. capseformis. By the latter character, 
by the more strongly developed and more numerous denticulations 
of the margin of the expansion, and by the greater convexity of the 
shell, T. florentina is distinguished from capseformis. The male of 
T. florentina is shorter, higher, and more swollen than that of T. 
capseformis. 
