LEMMUS 205 



rump ; intermixed white-tipped hairs iiripart a peculiar ash-grey 

 shade to the dorsum; a faint, broad, dark stripe marked on the 

 neck but less evident on the back. Sides somewhat Ughter 

 than cinnamon-rufous. Belly uniformly cinnamon, paler than 

 the sides. Fore-claws somewhat weaker than in other species, 

 but more robust than in Myopus; palms and soles densely 

 haired, the vestigial plantar tubercles completely hidden. 



Skull with zygomata less widely spreading than in other 

 species. Interorbital crest rather well developed. Braincase 

 relatively larger and smoother than in other Palsearctic forms, 

 L. obensis novosibiricus excepted. Length of interparietal about 

 one and a half times its width. Auditory bull£e relatively large 

 and inflated. 



For external and cranial dimensions, see tables at end of 

 volume. 



Remarks. — Vinogradov says that L. amurensis is sharply 

 distinguishable from all other Siberian species, and he calls 

 attention to the interest of the occurrence of a living member 

 of the genus in such a low latitude (about 52° N.). It is to be 

 hoped that a direct comparison will be made of this species with 

 Allen's L. o. ckrysogaster, a form apparently of similar small size 

 inhabiting the west coast of the Sea of Okhotsk near its northern 



extremity. 

 I 

 I 4. Lemmus paulus G. M. Allen. 



! 1914. Lemmus paulus G. M. Allen, Proc. New England Zool. Chib, 

 ' 5, p. 60. 



I Type. — Harvard University, Mus. Comp. Zool., No. 15,268; 



adult male, skin and skull, collected June 22, 1912, by J. Koren. 



Type locality. — Kalaschowo, near the mouth of the Kolyma 

 River, north-eastern Siberia. 



Range. — Known from the type locaUty and from Nijni 

 Kolymsk. 



Characters. — Size small, hind-foot 17-5 mm. ; condylo-basal 

 length 29-5 ; colour uniform. 



In summer pelage (represented by the type which still retains 



I a portion of the long winter coat on the lower part of the back) 



I the general colour above is buffy, largely mixed with blackish 



I on the head, becoming clearer posteriorly and at the sides. 



Individual hairs slaty for their basal three-fourths, with " pale 



buff" tips; mixed with these are wholly blackish hairs in the 



i dorsal area, but these disappear at the sides where the bufPy tips 



become more ochraceous ; sides of the neck and body and the 



ventral surface ochraceous, the hairs with slaty bases except 



on the chin, throat, anal region and forearms where they are 



white to their bases. Tail " pale buff " above, shghtly paler 



below. Ears small, round, quite concealed. Feet silverv with 



a dusky tinge. 



Winter pelage (represented by a specimen without skull 



