274 MICROTIN.E 



33. Evotomys idahoensis Merriam. 

 1891. Evotomys idahoensis Merriam, N. Anier. Fauna, No. 6, p. 66; 

 Bailey, Proc. Biol. Soc. Washington, 11, p. 131 ; Miller, " List," 

 1912, p. 212; " List," 1924, p. 403. 



Type.— U.S. Nat. Mus., No. ^tIIt '> adult female, collected 

 October 4, 1890. 



Type locality. — Sawtooth (or Alturas) Lake, east base of Saw- 

 tooth Mountains, Blaine County, Idaho. Altitude 7200 feet. 



Range. — Mountains of south central Idaho, between Snake 

 River and the Salmon. 



Characters. — Size medium (hind-foot 20 mm.) ; tail longer than 

 in E. gapperi. 



Mantle well defined, pale hazel, somewhat darkened by black 

 hair-tips ; face, sides and rump clear ash grey ; belly washed with 

 white or whitish. Ears sooty grey, without rufous tips. Feet 

 grey. Tail bicoloured, blackish above, grey below. 



Skull long, narrow and smooth, convex interorbitally ; zygo- 

 matic arches very oblique ; rostrum long ; posterior margin of 

 palate straight; pterygoids long and slender, longer, straighter 

 and further apart than in E. g. saturatus. Auditory bullae long 

 and laterally compressed, the basioccipital wide between them. 

 Incisors pale yellow. 



For external and cranial measurements, see table at end of 

 volume. 



34. Evotomys mazama Merriam. 



1897. Evotomys mazama Merriam, Proc. Biol. Soc. Washington, 11, 

 p. 71; Bailey, ibid., p. 132; Miller, "List," 1912, p. 212; "List," 

 1924, p. 404. 



Tj/pe.— U.S. Nat. Mus., No. 79913; adult male, collected 

 August 15, 1896. 



Type locality. — Crater Lake, Mount Mazama, Klamath County, 

 Oregon. Altitude 7000 feet. 



Range.- — -Crest of the Cascade Mountains in Oregon. 



Characters. — Size large (hind-foot 18-7 mm. ; basal length of 

 skull 23-3 mm.), tail long, about half length of head and body. 



Colour bright, ears not rufous. Mantle extending from front 

 of ears to base of tail, cinnamon rufous or hazel, shading gradually 

 into buffy grey of sides and face ; belly washed with buffy white. 

 Oval spot covering side glands in adult males slaty grey, more or 

 less frosted with white-tipped hairs. Feet greyish-white. Tail 

 sharply bicoloured, blackish above, whitish below. 



Skull broad and angular, with unusually fiat top ; long straight 

 rostrum, and abruptly spreading zygomata; pterygoids promi- 

 nent, wide and inflated at tips ; palate with a median posterior 

 projection. Auditory bullae large. Enamel of incisors orange. 



For external and cranial measurements, see table at end of 

 volume. 



