562 ORTMANN—NAYADES OF 
rest in the high mountains of North Carolina, and developed there 
into a good species. 
The type locality is French Broad and Swananoa rivers, Ashe- 
ville, Buncombe Co., N. Car. I have not been able to find this species 
there, for the French Broad is polluted in this region (lumber indus- 
tries on Davidson River). But I have rediscovered it in Big Pigeon 
River, at Canton, Haywood Co., N. Car., where it is not rare at the 
proper places. 
Specimens from “North and South Fork of the Cumberland 
River,” referred to this species, do not belong here, but are a form of 
A. marginata, with well-developed rugosities upon the posterior 
slope (atropurpurea Raf., ’31). 
Genus: PectAs Simpson (1900). 
Ortmann, ’14, pp. 45 and 65 (as subgenus). 
On account of the very peculiar glochidia I consider it better 
to retain Pegias as a genus, closely allied to Alasmidonta. 
43. PEGIAS FABULA (Lea), 1836. 
Margarita (Margaritana) fabula Lea, ’36—Alasmidonta fabula 
Ortmann, ’130, p. 311—Alasmidonta (Pegias) fabula Ortmann, 
"14, p. 65 (anatomy).—Pegias fabula Simpson, ’14, p. 473. 
A rare species in the upper Tennessee drainage, apparently pre- 
ferring smaller streams. Possibly it has been often overlooked on 
account of its small size and the peculiarity of being generally much 
eroded. I know it from the following localities. 
Wallen Creek, Lee Co., Va. (Walker coll.) ; Powell River, Dry- 
den, Lee Co., Va.; Big Mocassin Creek, Mocassin Gap, Scott Co., 
Va.; North Fork Holston River, Saltville, Smyth Co., Va.; North 
Fork Holston River, Holston, Washington Co. (Walker coll.) and 
Mendota, Washington Co., Va.; South Fork Holston River, Pac- 
tolus, Sullivan Co., Tenn. 
Type locality: Cumberland River, Tenn. 
Genus: StropHiITus Rafinesque (1820). 
Ortmann, ’120, p. 299. 
