46 MEMOIRS OF THE CARNEGIE MUSEUM. 



West of Mississippi: 

 Meramec River, Meramec Highlands, St. Louis Co., Missouri (N. M. Grier). 

 Black River, Black Rock, Lawrence Co., Arkansas (H. E. Wheeler). 

 White River, Cotter and Norfolk, Baxter Co., Arkansas (A. A. Hinkley). 

 Saline River, Benton, Saline Co., Arkansas (H. E. Wheeler). 

 Ouachita River, Arkadelphia, Clark Co., Arkansas (H. E. Wheeler). 

 Illinois River, Talequah, Cherokee Co., Oklahonaa (F. B. Isely). 

 Bayou Pierre, De Soto Parish, Louisiana (L. S. Frierson). 



Mississippi, Alabama, Georgia: 

 Pearl River, Mississippi (Juny collection). 



Buttahatchee River, Hamilton, Marion Co., Alabama (H. H. Smith). 

 Sipsey River, Texas, Marion Co.; Fayette, Fayette Co.; and Elrod, Tuscaloosa Co., Alabama (H. H. 



Smith). 

 Forks of Black Warrior River, Walker Co., and Black Warrior River, Squaw Shoals, Jefferson Co., 



Alabama (H. H. Smith). 

 Valley Creek, Toad vine, Jefferson Co., Alabama (H. H. Smith). 

 North River, Haglers Mill, Tuscaloosa Co., Alabama (H. H. Smith). 

 Cub Creek, Pine Hill, Wilcox Co., Alabama (H. H. Smith). 

 Cahaba River, Gurnee, Shelby Co., Alabama (H. H. Smith^. 

 Coosa River, Wetumpka, Elmore Co.; Weduska Shoals, Shelby Co.; Riverside, St. Clair Co., Alabama 



(H. H. Smith). 

 Choccolocco Creek, Calhoun Co., Alabama (H. H. Smith). 

 OoStanaula River, Rome, Floyd Co., Georgia (G. H. Clapp donor). 

 Conasauga River, Whitfield Co., Georgia (H. H. Smith). 



Distribution and Ecology in Pennsylvania (See fig. 5) : In Penns^'lvania this 

 species is rather local and not widely distributed. In the Ohio, Monongahela, 

 and Allegheny, it is rather scarce, and only isolated specimens turn up. In the 

 drainage of the Beaver it is a little more frequent, and the best places are at Edin- 

 burg and Pulaski. This would indicate, that the species prefers smaller rivers, 

 which is substantiated by the fact that it is rather abundant in the headwaters of 

 the Monongahefa, in Dunkard Creek in Pennsylvania, and in West Fork River in 

 West Virginia. In the upper Little Kanawha and in Elk River, West Virginia, 

 it is also frequent. 



This shell is found in coarse or fine gravel, generally not very deeply buried, 

 but young shells are often found in fine sand and even in mud. In a mill-race of 

 the ]\Iahoning, at Edinburg, among heavy rocks, about a dozen were collected, 

 all very large and ponderous. The best places are riffles with strong currents, 

 interrupted by patches of Dianthera americana. 



Scammon (1906, p. 314) reports this species in various ecological surroundings, 

 but says it prefers gravel and shingle, with a swift current, while Call (1900, p. 

 465) says that it delights in muddy bottoms, which, is surely not the case in Penn- 

 sylvania. 



