588 ORTMANN—NAYADES OF 
80. ‘TRUNCILLA STEWARDSONI (Lea), 1852. 
Umio stewardsom Lea, ’52.—Unio stewardsoni Lewis, ’71.—Trun- 
cula stewardsoni Simpson, ’14, p. 21. 
I think that what Walker (‘10a, pl. 3, f. 4) has figured as the 
db of T. lewisi is actually an old ¢ of stewardsoni. 
A rare species. The Carnegie Museum has specimens from the 
Tennessee at Knoxville, and Lewis reports it from this region; and 
there are also specimens from Clinch River, Clinton, Anderson Co., 
in the Carn. Mus. I found it myself in the Holston, at McMillan 
and Mascot, Knox Co., and at Holston Station, Grainger Co., Tenn. 
Type locality: “Chattanooga River, Tenn.” There is no such 
river in Tennessee. Generally, Lea’s “Chattanooga River” is the 
Chattooga River in northern Georgia (tributary to Coosa) ; but in 
the present instance this cannot be, since this species is not found 
in the Coosa drainage. 
81. TRUNCILLA LEWist Walker (1910). 
Unio foliatus Lewis, ’71.—Truncilla lewisi Simpson, ’14, p. 20. 
As stated above, Walker’s figure of the ¢ (’10a, pl. 3, f. 4) prob- 
ably belongs to T. stewardsont. _ 
I have found a single small male specimen (soft parts examined !) 
in the Holston, at Holston Station, Grainger Co., Tenn.,and another, 
somewhat larger one, in the Powell, at Combs, Claiborne Co., Tenn. 
These differ from the male of T. stewardsoni by a wider radial fur- 
row, with the two ridges confining it, more divergent. My speci- 
mens are not full grown, and even if they should be young females 
(as Walker suggested after examination of the one from the Hol- 
ston), they would present to us the shape of the male, as all young 
females do in the genus Trumcilla, exactly as the soft parts of young 
females resemble those of the males. 
The Carnegie Museum has (from the Hartman coll.) two fe- 
males, labeled: Tennessee River, Knox Co., Tenn. Lewis gives this 
form (as U. foliatus) from the Tennessee at Little River Shoals, 
below Knoxville; and Walker reports it from Clinch and Holston 
rivers in Knox Co. (also from Cumberland River, Burnside, Pulaski 
Co., Ky., but not found here by Wilson & Clark, ’14). 
