MYOPUS 185 



and long, attaining a lengtli of 23 mm. on back, slightly slioiter 

 on head; cars quite hidden. Entire pelage "deep neutral 

 grey," lined with white hairs, which isredominate ventrally ; 

 hairs of the mid-dorsum with a faint subterminal band of " russet " 

 giving a faint tinge to that region, but imperceptible except on 

 close inspection. Feet thinly haired, "drab"" with a silvery 

 tinge. Tail like the body above, whitish below. At the wrist, 

 ventially, is a cluster of stiff whitish hairs, which, however, do 

 not cover the palm ; tarsus well clothed with pale brownish hair. 



Skull slightly larger than in M. schisticolor and M. morulus; 

 m^ with outer triangle closed. 



For external and cranial measurements, see tables at end of 

 volume. 



6. i'Myopus brandti Tscherski. 



1879. ilyodes brandti Tscherski, HSBtcTin — Bull. E. Siber. Sect. 



Russ. Geogr. Soc, 10, Nos. 1-2, p. 22. 

 1S92. Lemmus obensis Tscherski, Mem. Acad. Imp. Sci. St. Petersb., 



[7], 40, p. 12. 

 1922. Myopus hrandtii Vinogradov, Ann. Mus. Zool. Acad. Sc. Russia, 



23, p. 373. 



Type. — -Zool. Mus. Russ. Acad. Sc. Leningrad, No. 1731 ; 

 rostral and palatal part of a skull with the molar series of the 

 left side, a piece of skin with the left fore-foot, and the right 

 fore-foot covered with skin. 



Type locality and horizon. — Cavern of NLshne-Udinsk, East 

 Sayan, 90 kilometres N.W. of Irkutsk, Siberia. Pleistocene 

 (soft parts jireserved in the frozen soil of the cave). 



Range. — Known only from the type locality and horizon. 



Characters. — -Fore-claws and skeleton of manus as in the 

 genus ; thumb-nail truncated distally without any incisure. 

 Salient angles of inner sides of upper molars sharp and not 

 truncated as in other species of Myopus or Lemmus ; crown of 

 m^ narrower than that of m^. Incisors more robust than in 

 M. schisticolor ; rostrum of the same length and palate furnished 

 with a small median sjsinous jirocess behind as in the latter 

 species. 



For cranial measurements, see table at end of volume. 



Remarks. — Although Tscherski came to the conclusion that 

 his Myodes brandti was indistinguishable from Lemmus obensis 

 the details recently jJublished by Vinogradov prove conclusively 

 that this interesting fossil is a member of the genus Myopus. 

 Its specific characters, however, are not very clear, and it is to 

 be hoped that further material will be acquired in order that the 

 precise relations of the fossil with the living forms may be 

 determined. 



