UPPER TENNESSEE DRAINAGE. 531 
from Grainger Co., Tenn., up the North Fork at Mendota, Washing- 
tom Coy Va. and Wie Moccasin’ Creeks ‘Scott (Co. Vas It has not 
been found in South Fork Holston, Watauga, or any of the eastern 
tributaries of the Tennessee, although the var. appressa goes to the 
lower Nolichucky and into the Little River drainage. 
In addition, it is in some of the tributaries of the lower Clinch: 
in Poplar Creek, Roane Co. (intergrading here with cuneolus ap- 
pressa) and in Emory River, at Harriman, Roane Co., Tenn. 
Type locality: Holston River, Tenn. (topotypes examined). 
6. FUSCONAIA CUNEOLUS APPRESSA (Lea), 1871. 
Unio appressus Lea, ’71.—Unio tuscumbiensis Lea, ’71—Unio 
flavidus Lea, ’71—Pleurobema tuscumbiensis Simpson, ’14, p. 
748. 
There has been great confusion about this form, for the reason 
that the type-set in the U. S. Mus. (examined by myself) contains 
three specimens, of which only one, the figured type, is this, while 
the other two belong to Levingtonia dolabelloides conradt (Van.). 
But several authors seem to have taken the latter as the types, and 
thus, for instance, Pleurobema appressum Simpson (’14, p. 747) is 
not this, but Lexvingtonia dolabelloides conradt. 
The figured type of Lea is a more swollen form of F. cuneolus, 
and resembles the latter in every respect except obesity. I have 
drawn the line between the two at the diameter of 50 per cent. of the 
length, and specimens with this diameter, and over, I call F. cuneolus 
appressa. 
This variety belongs to the larger rivers. I have not seen it from 
the Powell, and in the Clinch it turns up for the first time below the 
mouth of the Powell, at Offutt, Anderson Co., Tenn., but it goes into 
a smaller tributary of the lower Clinch, Poplar Creek, Roane Co., 
associated here with typical cuneolus. In Emory River, only cume- 
olus has been found. In the Holston, appressa turns up first at 
Austin Mill, Hawkins Co., Tenn., associated and intergrading with 
typical cuneolus. I also found F. cuneolus appressa in the Noli- 
chucky, at its mouth, and then it seems to be the prevailing form in 
the Tennessee at and below Knoxville. 
