264 Mr. 0. Thomas on 



Type. Adult male. Original number 108. Collected 

 Utii June, 1908. 



I have been much puzzled as to where this peculiar little 

 vole should be placed. It differs from all the members of 

 Vitymys by its more numerous mammae, and in this respect, 

 as in locality and the details of the molar pattern, it shows 

 affinity with FliaiomyH. But there is nothing very essential 

 in the difference of molar pattern, while the general shape of 

 the skull, the external proportions, and the moderate claws 

 are all so much more like Pitymys than Phaiomys, that 

 I provisionally place it with the former, in which it is 

 geographically a connecting-link between the European and 

 American members. 



19. Microtus (Alticola) argurus, sp. n. 



$ . 102. Hissar Mts., 100 miles E. of Samarkand. 

 9500'. 14th June, 1908. Type. 



A pale species, with an unusually long white tail. 



Size about as in M. blanfonli, the only other long-tailed 

 species. Fur fine and soft; hairs of back (in summer pelage) 

 about 7-8 mm. in length. General colour above "ecru- 

 drab " ; under surface white, the slaty bases of the hairs 

 showing through ; a line of cream-buff marking the junction 

 of the upper and lower colours on the sides. Hands and 

 feet white. Tail unusually long, slender, thinly haired (in 

 summer), lightly pencilled, wholly white above and below. 

 Mammae 2 — 2 = 8. 



Skull not unlike that of J/. {A.) wortkingtoni, Miller, 

 allowing for the fact that the type is barely adult. Bullae 

 rather smaller. 



Teeth of the typical Alticola structure, but not very highly 

 specialized, as the posterior lobe of ?n^ is not so long as it 

 often is, and is also, with the rest of the teeth, thicker, its 

 thinness being a characteristic of the most specialized forms 

 of Alticola. Pattern about as in M. blanfordi *. 



Dimensions of the type (barely adult) : — 



Head and body 93 mm. ; tail 50 ; hind foot 19; earl5"5. 



Skull : greatest length 25 4 ; nasals 7'2 ; interorbital 

 breadth 3'9 ; palatilar length 12; diastema 7"4 ; palatal 

 foramina 4*6; upper molar series (crowns) 6"2. 



Hah. and type as above. 



This striking vole is readily distinguishable by its very 

 long tail from all the species of Alticola except M. blanfordi, 

 which approaches it in tail-length but is very much darker 



* Figured by Blanford, J. A. S. B. 1. pt. 2, pi. i. (1881). 



