A NEW VOLE FROM EASTERN MONGOLIA 



By GERRIT S. MILLER, Jr. 



I With One Plate) 



On his return to Tientsin from a recent expedition to the 

 region in eastern Mongolia, north of Kalgan, Mr. Arthur de C. 

 Sowerby, who has for several years been making zoological explora- 

 tions in the interests of the Smithsonian Institution, wrote me as fol- 

 lows concerning a peculiar yellowish species of Microtus: 



In addition to Microtus angustus Thomas, obtained by Anderson in the 

 same region, I obtained several specimens of what I take to be a new vole. 

 This animal I found to be an inhabitant of the open country, where it lives 

 in holes in the walls of the camps and huts ; at least, it was only around 

 buildings that I could catch any. This is probably the reason why Anderson 

 did not secure any, as he collected in exactly the same locality as I did. 

 If you find it to be a new species would you mind naming it after my assistant 

 Warrington, who " spotted" it first? He was sitting in our tent and heard a 

 noise. On looking up he saw the little animal run out under the flap. We 

 promptly got traps out, and inside an hour had two or three specimens. This 

 vole is diurnal while M. angustus is nocturnal. 



The animal proves to be a hitherto undescribed member of the 

 subgenus Phaiomys, forming with M. brandti (Radde) a group in 

 some respects intermediate between typical Phaiomys and true 

 Microtus. In compliance with Mr. Sowerby's request it may be 

 known as : 



MICROTUS WARRINGTONI, new species 



Type. — Adult male (skin and skull) No. 1 75861 U. S. National 

 Museum. Collected at Tabool, Mongolia (altitude 4,000 feet), 100 

 miles north of Kalgan, August 13, 1912, by Arthur de C. Sowerby. 

 Original number, 508. 



Diagnosis.- — Like Microtus (Phaiomys) brandti (Radde) in color 

 and in its combination of the external and dental peculiarities of 

 Phaiomys with an unmodified, true-Micro tus-Uke skull ; size con- 

 siderably greater than in M. brandti, the difference between the two 

 species about like that existing between M. (PJiaiomys) mandarinus 

 and M. (P.) johannis. 



Color. — Upperparts cream-buff faintly but evidently " lined " with 

 blackish and irregularly darkened by appearance at surface of the 

 blackish-slate hair bases (2.5 mm.), the general effect not far from 



Smithsonian Miscellaneous Collections, Vol. 60, No. 28 



