FIELD BOOK OF MAMMALS 



Howell believes that more than one litter of young is raised 

 annually and gives the number in a litter as from four to nine, 

 the usual number being five or six (for longicaudus one to 

 three). None of these Mice hibernate and it is unlikely that 

 any of them are of any economic importance, since most of the 

 species do not come into conflict with agricultural interests. 



Genus Evotomys ^ 

 Dentition: Incisors, \; Canines, g ; Premolars, %\ Molars, f = i6. 



Red-backed Mouse. — Evotomys gapperi 



and related forms 



Names. — Red-backedj_Mouse ; Red- backed Vole. Plate 

 XXX. 



General Description. — A small to medium-sized Mouse 

 with small eyes; low ears, just reaching above fur; short tail; 

 pelage rather long and usually characterized by a broad, red- 

 dish dorsal band; habitat cool forests and brushy areas. 



Color. — vSexes colored alike, a slight seasonal variation. 



Upperparts. — Winter: dorsal band from crown to base 

 of tail bright chestnut, sprinkled with black; sides buffy 

 ochraceous ; feet clear gray ; tail bicolor, brownish above, black- 

 tipped, grayish buff below. 



Underparts. — Pale buff. 



Summer pelage slightly darker. 



Immature pelage with less bright tones and more subdued 

 coloration. 



Measurements. — Sexes of equal size. Total length, 5.6 

 inches; tail vertebrae, 1.5 inches; hind foot, .72 inch. 



Geographical Distribution. — Northern portions of wooded 

 North America. 



Food. — Green vegetation and seeds, stems, leaves, and soft 

 parts of grass and low-growing plants. 



Enemies. — Snakes, Hawks, Owls, Weasels, Foxes, Skunks, 

 and most small carnivores. 



^The only revision of this genus now available is by Vernon Bailey. 

 Proceedings Biological Survey Washington, Vol. XI, pp. 1 13-138, 1897. 

 Some forms have been described since then and the ranges are not very 

 well known. 



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