NO. 14 NEW .MAMMALS FROM SIBERIA — HOLLISTER 3 



General characters. — Like A. mongolica, but smaller and grayer, 

 with much smaller skull. 



Color of type. — General color of upperparts pale drab-gray, mure 

 brownish on rump; sides light -ray; sides of face and underparts, 

 and rump stripes, pure white. Legs -ray outside, white inside : arms, 

 hands, and feet white. Tail brownish above for two-thirds its length, 

 then band of grayish-white, band of black, and tip of pure white; 

 below grayish-white, with black sub-terminal band and white tip. 



Skull and teeth. — Skull like that of mongolica, but very much 

 smaller, with broader rostrum ; teeth smaller. 



Measurements of type. — Head and body, 143 mm. ; tail vertebrae, 

 183 ; hind foot, 66. Skull compared with skull of adult female . /. in. 

 longior, the latter in parentheses : Greatest length, 36 I 3* 1.5) ; o mdyli >- 

 basal length, 34 (37.5) ; zygomatic breadth, 23.5 (26) ; upper tooth 

 row, alveoli, 7.5 (8.4). 



Remarks. — This new jerboa seems related only to . /. mongolica and 

 A. in. longior. It is possibly confined to the isolated Chuisaya Steppe. 

 Two specimens were collected. 



PHODOPUS CREPIDATTJS, sp. nov. 



Type from Chuisaya Steppe (eight miles south of Kosh-Agatch) , 

 Altai District, Siberia; altitude 7300 feet. No. 175480 United States 

 National Museum ; skin and skull ; adult J 1 . Collected July 28, 1912, 

 by N. Hollister. Orig. No. 4393. 



General characters. — Palms and soles completely haired. Exter- 

 nally resembling P. songarus and P. campbelli. Differs from songarus 

 in absence of shoulder stripes, faintness or lack of median stripe on 

 crown and nape, strong suffusion of huffy on sides and underparts. 

 and much smaller, slenderer skull, with large audital bullae. Differs 

 from campbelli in shortness of the dorsal stripe, which stops abruptly 

 on rump fully an inch from base of tail ; tail buffy, not silvery white ; 

 and skull long and slender, with large audital bullae. 



Color of type. — Upperparts -ravish wood-brown, the hairs wood- 

 brown tipped with blackish; underfur dark slate; a narrow blackish 

 stripe from between shoulders to rump. Lips and cheeks creamy 

 white; ears dark brown and buffy outside, white inside. Tail buffy 

 near root, tip and lower side white. Shoulders bright buff, the three 

 light areas on body and entire underparts whitish, with strong suffu- 

 sion of buffy. 



Skull. — Skull smaller and narrower than a skull of songarus from 

 Akmolinsk, Siberia, with greater interorbital breadth and much 



