82 MEMOIRS OF THE CARNEGIE MUSEUM. 



while Call (1885) says: "from western New York to Kansas; south to the Holston 

 River, Tennessee." 



Very likely, this form is present in western New York in the Allegheny-drain- 

 age, judging from its presence in Pennsylvania both in Warren and McKean Cos., 

 although Marshall (1895) reports it only from Lake Erie, no doubt referring to 

 the variety pauperculum. In Ohio it is found all over the state (Sterki, 1907«), 

 but definite reports are mainly from smaller streams. ^'^ It is known from the 

 Mahoning River (Lea, Dean, 1890), Tuscarawas River (Dean, Sterki), Scioto 

 River, and from Columbus (Lea). As in Pennsylvania so in Ohio it crosses 

 over into the lake-drainage, and is found in the Cuyahoga (Dean) and Mau- 

 mee-drainage (Carnegie Museum). It occurs also in the lake-drainage in 

 southern Michigan (Walker, 1898). It is common in Indiana, and there also 

 crosses into the lake-drainage, St. Marys and St. Josephs Rivers (Call, 1900). 

 Wilson & Clark (1912, p. 42) observe that coccineum is found in the headwaters of 

 the Kankakee River in Indiana, but that in the lower Kankakee and in the Iroquois 

 River in Illinois it passes into a form belonging to the ohliquum-growY). In Illinois 

 the same conditions seem to prevail (Baker, 1906) or at any rate it goes far up 

 toward the north in that state. 



As our localities show, this form is found in the tributaries of the Ohio in 

 West Virginia and eastern Kentucky. Other records from Kentucky and from 

 Tennessee are missing, except Call's statement, that it is found in the Holston. 

 It is, indeed, present in the Holston and in the Clinch, but is quite rare there, and 

 closely connected with the variety catillus. 



Farther to the west and southwest there is the record from Coon River, Dallas 

 Co., Iowa (Marshall, 1895), that from the drainage of Turkey, Wapsipinicon, and 

 Volga Rivers, northeastern Iowa (Geiser, 1910), and that from Missouri (Utter- 

 back, 1916). It is said to be present in Kansas (Scammon, 1906), and is in northern 

 Arkansas (see our specimens and Meek & Clark, 1912) and even in the Ouachita 

 River, in Clark Co. (Wheeler, 1918). But in this direction, the limit of its range 

 is obscure. It seems, that in this region likewise it prefers smaller streams, but 

 this needs further investigation. 



^^ Lea gives it from the Ohio at Marietta, Washington Co., Ohio, and it is in the Cincinnati-list 

 (Harper, 1896); but these records are to be doubted. I have never found it in the Ohio, and the large 

 sheU-heaps of the clam-diggers examined by myself at various places never yielded a single individual of 

 tills shell, 



