260 



MEMOIRS OP THE CARNEGIE MUSEUM. 



empties into the outlet, the water of the former being backed up and transformed 

 into a quiet pool. It lives here in mud. 



This species has been reported from western New York in the Erie Canal in 

 Onondaga Co., and in the Genesee Canal (Marshall, 1895). It is possible that 

 these localities may later be discovered to be connected with the Pennsylvania!! 



Fig. 27. 



• Toxolasma parvum. 



■ Eurynia fabalis. 

 + Eurynia iris. 

 X Eurynia iris novi-eboraci. 



locality, and this in turn with the western localities, when the species is looked for 

 at favorable habitats (canals, sloughs, etc.). In the state of Ohio it is not rare, 

 and is found i!! both drainages, and also in Lake Erie (Sterki, 1907a; Walker, 

 1913, p. 21). It is know!! i!! the lake-drainage in southern Michiga!! (Walker, 

 1898), and is found practically all over Indiana (Call, 1896a) and Illinois (Baker, 

 1906). Here it does not enter the lake-drainage, except in the Maumee River 

 (Call). It is knowi! from Fox River, Wisconsin, from southern Minnesota (Call, 

 1885; Gra!!t, 1886; Holzinger, 1888), from Iowa (Pratt, 1876; Witter, 1878; 

 Call, 1895; Marshall, 1895; Geiser, 1910). Thence it extends southward, and is 

 found in Missouri (Utterback, 1916), i!! Kansas (Sca!nmo!!, 1906), Arkansas (Call, 

 1895; Wheeler, 1918; see also Carnegie Museum), Oklahoma, and as far south 

 as Texas (Singley, 1893). However, in this region a closely allied species, T. 

 texasense (Lea) turns up, and this seems to gradually replace it (see Simpson, 

 1900, p. 564, footnote 2) and possibly the two forms intergrade. According to 

 Vaughan (1893) they r!i!! into each other in northwestern Louisiana. 



