576 ORTMANN—NAYADES OF 
has it from Tennessee River, Little River Shoals, Knox Co., Tenn. 
I found it chiefly toward the headwaters, in Powell, Clinch, and Hol- 
ston. In the Powell, it goes up to Combs, Claiborne Co., Tenn. ; in 
the Clinch, to Cleveland, Russell Co., Va.; in the North Fork Hol- 
ston, to Hilton, Scott Co., Va.; in the South Fork, to Pactolus, Sul- 
livan Co., Tenn. It seems to be absent from the eastern tributaries 
of the system. 
Type locality: Ohio River. 
65. EuryniA (MicroMyA) TRABALIS (Conrad), 1834. 
Unio trabalis Conrad, ’34.—Eurynia (Micromya) trabalis Ortmann, 
Extremely rare. I found a single specimen in Clinch River, at 
Speer’s Ferry, Scott Co., Va.; another one in South Chickamauga 
Creek, Ringgold, Catoosa Co., Ga.; and three specimens in Hiwassee 
River, at Austral, Polk Co., Tenn. At the first locality, it was asso- 
ciated with the next species. 
The only difference of E. trabalis and perpurpurea is, that the 
former has white, the latter purple nacre. The specimens from the 
Hiwassee are exceptionally large, and do not taper so much behind 
as usual. 
This species seems to have its metropolis in the Cumberland 
system (Wilson & Clark, ’14). Call cites it. from Clinch and Powell 
Rivers in Tennessee, but Lewis does not mention it from the “ Hol- 
ston”? (= Tennessee), and I have never seen a trace of it in the 
whole Holston drainage. According to Hinkley, it is rare in the 
mussel shoals of the Tennessee in Alabama; the Carnegie Museum 
has one specimen from Paint Rock River, at Paint Rock, Jackson 
Co., Ala. It may be that my localities in Chickamauga Creek and 
Hiwassee River are connected with the range in northern Alabama. 
Type locality: ? 
66. Eurynta (MIcroMYA) PERPURPUREA (Lea), 1861. 
Unio perpurpurea Lea, ’61—Euryma perpurpurea Ortmann, 713), 
p. 311.—Eurynia purpurpurea Goodrich, ’13, p. 94.—Lampsilis 
perpurpurea Simpson, *14, p. 133.—Eurynia (Micromya) per- 
purpurea Ortmann, ’15, p. 63 (anatomy). 
’12b, p. 340 (anatomy ).—Lampsilis trabalis Simpson, ’14, p. 132- 
