UPPER TENNESSEE DRAINAGE. 529 
also goes into the lower Powell, up to Claiborne Co., Tenn. From 
the Holston, it goes in the lower parts of the North and South Fork: 
but at and near its upper limit, it always intergrades with the next 
form (bursa-pastoris). 
Type locality: Caney Fork River, Tenn. (and Holston River, 
Tenn.). (Thus it seems to exist also in the Cumberland drainage, 
but this requires further investigation. Wilson and Clark, ’14, do 
not mention it.) 
4. FUSCONAIA PILARIS BURSA-PASTORIS (Wright), 1896. 
Unio bursa-pastoris Wright, ’96—Unio kirtlandianus Pilsbry & 
Rhoads, ’96.—Fusconaia bursa-pastoris Ortmann, ’13a, p. 90 
(anatomy), and ’13b, p. 311—Fusconaia bursa-pastoris Good- 
rich, 13, p. 93.—Quadrula bursa-pastoris Simpson, ’14, p. 890. 
This is the compressed headwaters-form of F. pilaris, connected 
with it through the intermediate form /esweuriana. It has the same 
relation to F. pilaris, as has F. kirtlandiana (Lea) of the upper Ohio 
drainage to F. subrotunda; it is practically the same thing, except 
that it does not reach the size of it, and does not develop the “ wing” 
seen on the posterior upper margin of kirtlandiana. It is perfectly 
clear that the form mentioned by Pilsbry & Rhoads from Watauga 
River, Johnson City, Tenn., is this, and, indeed, I have found it 
very close to this locality. 
The diameter of this form is less than 45 per cent. of the length, 
and it appears as if the lack in this direction is compensated by a 
greater circumference of the shell, bursa-pastoris often reaching a 
size (length and height) not seen in either pilaris or lesweuriana. 
The metropolis of this form is in Clinch River; a few specimens 
have been found in the lower Clinch, in Knox and Anderson Cos. 
(associated with lJesweuriana and even pilaris); farther up, from 
Claiborne Co., Tenn., into Virginia, it becomes more and more 
abundant, and north of the state line, where Jeswewriana disappears 
(only found at Clinchport), it is developed as a pure race, going up 
into the headwaters as far as Cedar Bluff, Tazewell Co., Va. In 
Powell River, similar conditions prevail; in the lower Powell it is 
found associated and intergrading with Jesweuriana, but north of the 
