TWO NEW MAMMALS FROM THE SIBERIAN ALTAI 

 By N. HOLLISTER. 



The following" two species of Siberian mammals complete the list 

 of novelties obtained by the expedition organized in the interests oi 

 the National Museum and the Museum of Comparative Zoology, in 

 191 2, by Prof. Theodore Lyman, of Harvard University. 



APODEMUS NIGRITALUS, new species 



Type from Tapucha, Altai Mountains, Siberia ( 125 miles south- 

 east of Biisk, and 50 miles northwest of Ongudai). United States 

 National Museum No. 175 164, skin and skull of J 1 adult (teeth 

 considerably worn). Collected August 6, 1912, by N. Hollister; 

 original No. 4438. 



General characters. — A member of the speciosus-peninsulce group. 

 Larger and darker colored than Apodemus peninsulce; tail relatively 

 much shorter, considerably less than head and body. 



Color.- — Upperparts dark brown, finely lined with blackish-brown ; 

 darker on head ; nose blackish. Some specimens show considerable 

 chestnut color on rump. Sides lighter than back, with less mixture 

 of blackish-brown, sharply marked from the grayish-white belly. 

 Hands and feet grayish-white, a sharply marked blackish ring- 

 around ankle separating the colors of leg and foot. 'Fail sharply 

 bicolor. 



Skull and teeth. — Skull like that of Apodemus peninsulce, but 

 averaging heavier and larger, the interpterygoid space constantly 

 wider. Teeth essentially as in peninsulce. 



Measurements. — Type: Head and body, 122 millimeters; tail 

 vertebrae, 102; hind foot, without claws, 25. Average of five adults 

 from type locality, compared with average of rive adults of .1. 

 peninsula' from Shansi, the latter in parentheses: Head and body. 

 1 10 (87) ; tail vertebrae, <)4 (91) ; hind foot, 23.4 (22.8).' Skull of 

 type : Greatest length, 29 ; condylobasal length, 27.5 ; zygomatic 

 breadth, 14.8; palatal length, 15.2; nasals, 11. 5; length of mandible. 

 17 ; upper tooth row, 4.1 ; lower tooth row, 4.0. 



Remarks. — Two species of Apodemus occur together in the Altai. 



Smithsonian Miscellaneous Collections, Vol. 60, No. 24 



