The American Voles of the Genus Evotomys. 117 



gnpperl ' Near Lake Simeoe, Ontario, Canada. 



" ochraceus ]\Iount Washington, New Hampshire. 



" rlioadsi Mays Landing, New Jersej'. 



" loringi Portland, North Dakota. 



" galet Ward, Colorado. 



" saluratus Nelson, British Coknnbia. 



bn'vicaudus Custer, Black Hills, South Dakota. 



caroliuengis Roan INIountain, North Carolina. 



ungava Fort Chimo, Ungava. 



idahoensis Sawtooth Lake, Idaho. 



mazama . Crater Lake, Oregon. 



obscurm Prospect, Oregon. 



califomicus Eureka, California. 



occidentalls Aberdeen, Washington. 



nivarins Mount EUinor, Olympic Mountains, 



Washington. 

 proteus Hamilton Inlet, Labrador. 



Key to Species and Subspecies of Evotomys. 



Ears distincthj riifons-ilppi'd, not grog or daxJcg. 



Tail more than twice the length of hind foot. 

 Dorsal stripe not sharply defined. 



Ears small, scarcely XMotruding from fur, dorsal 



area ill defined, dull chestnut uvgava. 



Ears large, prominent above fur, dorsal area dark 

 chestnut, blending with color of sides (winter 



pelage) carolmensis. 



Dorsal strij^e sharply defined. 



Tail scarcely more than twice the length of hind 

 foot, about 27 per cent, of total length. 



Dorsal strijie bright chestnut, with scattered 



black hairs, color sometimes dichromatic, .gapperi. 

 Dorsal stripe dull rusty rufous without black 



hairs, color not dichromatit- ochraceus. 



Tail considerably more than twice the length of 

 hind foot, about 30 per cent, of total length. 

 Large, hind foot 20 or more ; colors dichro- 

 matic, a red and a gray pelage proteus. 



Smaller, hind foot less than 20; not dichro- 

 matic. 

 Skull with pronounced superciliary ridges 



in adults, size medium galei. 



Skull without pronounced superciliary 



ridges in adults, slightly larger saluratus. 



Tail less than twice the length of hind foot. 

 Dorsal stripe sharply defined, tail bicolor. 



Size large, foot 20 mm., dorsal stripe ferruginous. 



