RED-BACKED MOUSE 



along "Crest of the Cascade Mountains in Oregon." 

 (Bailey) 



Dusky Red-backed Mouse. — Evotomys ohscurus Merriam. 

 "A rather large, grayish species, with small gray ears and 

 indistinct markings; side glands inconspicuous, but easily 

 discovered on blowing apart the fur. . . . Upperparts 

 olive-gray, with an ill defined dorsal area of cinnamon- 

 rufous, obscured by black hairs; lower part of sides and 

 face clear gray; belly washed with dull buff; ears dusky, 

 not rufous tipped; feet dusky gray; tail distinctly bicolor." 

 Total length, 6.2 inches; tail vertebras, 1.9 inches; hind 

 foot, .70 inch. Found on "West slope of the southern 

 Cascade Range and northern Sierra Nevada in southern 

 Oregon and northern California." (Bailey) 



California Red-backed Mouse. — Evotomys californicus Mer- 

 riam. 

 Very large, dark, and long-tailed. "Upperparts dark 

 bister or sepia, becoming dusky on rump and dull, dark 

 chestnut on back; dorsal area indistinct and shading 

 gradually into color of sides; oval patches of dense fur 

 covering side glands plumbeous in slight contrast to surround- 

 ing fur; belly pale buffy or soiled whitish, darkened by the 

 plumbeous under fur; tail sharply bicolor, blackish above 

 and at tip all round, whitish beneath; feet whitish or 

 but sHghtly dusky; ears dusky, with no rufous or Hght- 

 colored hairs." Total length, 6.4 inches; tail vertebras, 

 2 inches; hind foot, .84 inch. Found in "Coast strip of 

 Oregon and northern California." (Bailey) 



Western Red-backed Mouse. — Evotomys occidentalis Merriam. 

 Smaller than californicus; tail long; dorsal area indistinct. 

 Upperparts (summer) dull, burnt umber to dark chestnut, 

 mixed with black; sides dark gray suffused with buffy; 

 tail almost unicolor, dusky; feet dusky; underparts buffy. 

 Total length, 5.8 inches; tail vertebrae, 1.8 inches; hind 

 foot, .72 inch. Found in "Coast and Puget Sound region 

 of Washington and southern British Columbia." (Bailey) 



Olympic Red-backed Mouse. — Evotomys nivarius Bailey. 

 Resembling occidentalis but color lighter . and brighter. 

 Upperparts with distinct band of light chestnut; sides 

 dark gray; tail bicolor, feet and underparts whitish. Total 

 length, 6 inches; tail vertebrae, 2 inches; hind foot, .72 inch. 

 Found on "Mt. Ellinor and probably other high peaks in 

 the Olympic Mountains." (Bailey) 



Labrador Red-backed Mouse. — Evotomys proteus Bangs. 

 Size large, color variable; ear and hind foot large. Usual 

 color of upperparts sepia, merging into smoke-gray mixed 

 with yellowish on sides; feet and underparts grayish; tail 

 faintly bicolor. Sometimes dorsal region is bright_ chest- 

 nut. Total length, 6.5 inches; tail vertebrae, 2 inches; 

 hind foot, .82 inch. Found about Hamilton Inlet, Labra- 

 dor. 



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