206 MICBOTIN^ 



taken at Nijni Kolymsk, October 31, 1911) about 24 mm. long 

 on the rump. Colour nearly uniform ochraceous buff above and 

 below, slightly deeper on the rump paler on the belly. Dorsal 

 region from muzzle to middle of back darkened by a considerable 

 mixture of black hairs which disappear posteriorly. Throat 

 nearly wliite; fore-arms and legs below pale buffy. 



Skull nearly a fifth smaller than in L. obcnsis, shghtly smaller 

 than in L. lemmus. Anterior palatal foramina strongly and 

 abruptly contracted behind. Palate produced medially to form 

 a weU-marked sharp process, instead of being blunt as in L. 

 lemmus. 



Incisors nearly milk-white with a faintly buffy tinge, instead 

 of being clear yellow as in L. lemmus; m^ differs from that of 

 the latter species in having the enamel walls of the prisms nearly 

 straight instead of curved, and the prisms themselves slope 

 antero-internaUy instead of being nearly transverse. 



For cranial and external measurements, see tables at end of 

 volume. 



Remarks. — No material seen. Mr. AUen says the species is 

 remarkable for the uniform coloration of both summer and 

 winter pelages, the white incisors, and the compressed enamel 

 walls of m^. " It does not closely resemble L. lemmus nor the 

 large L. obcnsis. To judge from descriptions alone, it is similar 

 in many of its characters to L. minusculus, described by Osgood 

 from the base of the Alaska Peninsula, but seems less brightly 

 coloured, though of about the same size." It is probably the 

 Siberian representative of L. minusculus. 



1894. 

 1896. 



5. Lemmus nigripes True, 

 [. Myodes nigripes True, Diagnoses of new North American 

 Mammals, p. 2; reprinted Proc. U.S. Nat. Mus., 17, 1894, p. 242. 

 ;. Lemmus nigripes Miller, N. Amer. Fauna, No. 12, p. 37 ; " List,'* 

 1912, p. 206 ; " List " 1924, p. 396. 



Type. — U.S. National Museum. 



Type locality. — St. George Island, Pribilof Islands, Alaska. 



Range. — Known only from the type locahty. 



Characters. — Essential characters and size nearly as in L. 

 lemmus; colour subdued. Upper surface dark brown, clothed 

 with a mixture of dark brown, dusky, and bright ochraceous 

 hair-tips darkest on top of head palest below and behind ears 

 and on the rump. Tip of muzzle black. Sides of muzzle, upper 

 lips and flanks bright ochraceous. Under parts didler and paler 

 irregularly darkened by the slaty bases of the hairs. Chin 

 whitish. Hands and feet dark brown to blackish; palms and 

 soles hairy, the pads at bases of toes not completely concealed. 

 Tail dark brown above, paler below. 



For external and cranial measurements, see tables at end of, 

 volume. 



