42 MEMOIRS OF THE CARNEGIE MUSEUM. 



Tennessee River, Florence, Lauderdale Co., Alabama (H. H. Smith). 

 Mississippi River, Muscatine, Muscatine Co., Iowa (Hartman collection). 

 Sheyenne River, Argusville, Cass Co., North Dakota (S. M. Edwards). 

 Ilinkston Creek, Columbia, Boone Co., Missouri (D. K. Gri'ser). 

 Platte River, Garretsburg, Buchanan Co., Missouri (\V. I. Uttcrback). 

 Lake Contrary, St. Joseph, Buchanan Co., Missouri (W. I. Utterback).'^ 

 Wakarusa River, LawTence, Douglas Co., Kansas (R. L. Moodie). 



Cliikaskia River, Tonkawa, Kay Co.; North Fork Canadian River, Weleetka, Olcfuskee Co.; Deep 

 Fork Canadian River, Okmulgee, Okmulgee Co., Oklahoma (F. B. Isely). 



Distribution and Ecology (See hg. 5). Type locality: Ohio River (Rafinesque) 

 according to Vanatta, Salt River, Kentucky. 



Two specimens only have been found in Pennsylvania; one in the Ohio River, 

 just above the Ohio state hne, the other in Lake Erie. The first was found in 

 sandy-muddy bottom in a quiet eddy in a riffle, the second (a dead shell) in fine 

 sand, the environment characteristic of Presque Isle Bay. According to Baker 

 (1898a, p. 85) this species prefers the muddy and sandy bottoms of lakes and larger 

 rivers, and Call (1900, p. 490) calls it a mud-inhabiting shell, while Scammon 

 (1906, p. 252) says that in Kansas it is not particular as to station, but prefers 

 sand. Apparently, it does not find congenial habitats in Pennsylvania, except in 

 Lake Erie and in the Ohio. Its utmost upstream migration has barely reached 

 our state. 



Farther down the Ohio, it is also not very abundant, but it is present. In 

 the slack water of the lower part of Middle Island Creek, I have seen a number 

 of dead shells, and here it goes up as far as the slack water, about 5 miles, to just 

 below Union Mills. Also farther down it is not abundant, and distinctly prefers 

 sandy or muddy bottom to gravel. It does not ascend far into the tributaries, 

 but it goes into the lower Muskingum and to Wolfe Creek. It is not in the Tus- 

 carawas, according to Sterki (1907o, p. 390). In western Ohio and in southern 

 and northwestern Indiana it is more widely distributed. Here it crosses over into 

 the Lake Erie-drainage (Ohio Canal, Sterki), and into the lake (Sterki, and Walker, 

 1913). It occurs also in Beaver Creek, Lorain, Lorain Co., Ohio (Dall & Simpson, 

 1895), and in Michigan (Walker). It extends westwards and southwards to 

 Minnesota, Iowa, Kansas, Oklahoma, northeastern Texas, and northern Louisiana. 

 It also crosses over into the drainage of the Red River of the North (Winnipeg, 

 Canada). There are no records from south of the Ohio, but the Carnegie Museum 

 has it from the Tennessee in northern Alabama. From Alabama, there is only a 

 single, doubtful and indefinite, previous record (Call). 



Thus it seems that the center of this species is in the Mississippi and lower Ohio. 



^^ This is the var. contraryensis of Utterback, a local phase. 



