502 Mr. 0. Thomas on Mammals 



Mongolian ])lateau, I remarked on the shortness o£ its tail- 

 liairs, but laid no stress on the character, supposing it to be 

 due to season. But the present series was collected at 

 exactly the same time of year (end of July and beginning of 

 i\ugust), and it is now evident that the material difference in 

 tie bu?hiness of the tail is a genuine local character. The 

 terminal tail-hairs of wmhratits are 10—12 mm. in length, 

 those of ramosus 16-20, as is also the case in the much paler 

 typical C. mongolicus. 



It seems probable that the plateau Ibrm umhratus may 

 deserve to be separated specifically on account of its less 

 bushy tail, while ramosus would remain as a darker eastern 

 subspecies of ihongolicus, inhabiting Southern Mantchuria. 



7. Arctomys s'lbiricus^ E.adde. 

 3 S (adult and two young). Khingan Mts. 



8. Mus caraco, Pall. 



$ . Khingan Mts. 



^ (young). Ciiu Chia Tai, Kirim Province. 



This would appear to be a short-footed Eastern represen- 

 tative of M. norvegicus, but the only adult specimen has lost 

 its skull, so that I am unable to give any definite opinion 

 about it. 



9. Mus wagneri manchu, subsp. n. 



(f*, 2 ? . Fan Chia Tun, Kirim Province. 



6 c? , 4 ?. Cliu Chia Tai, Kirim Province. 



A still darker form than mongolium of the pale Central- 

 Asian M. wagneri. 



General colour above smoky drab, decidedly darker along 

 the middle of the back. Under surface white, generally in 

 marked contrast to the colour of the sides, but there is often 

 a drabby suffusion over the belly, which sometimes even clouds 

 the sharp definition of the upper and under sides. Proectote 

 of ears a little darker than the head. Hands and feet dull 

 white. Tail greyish drab above, lighter below. 



Skull as usual. 



Dimensions of the type (measured in the flesh) : — 



Head and body 85 mn).; tail 0*6', hind foot 16*0 ; ear 11-5. 



Greatest length of skull 21-3. 



Hoh. (^of type). Chu Chia Tai, Kirin Province. 



Type, Adult female. Original number 8y. Collected 22 

 August, 1908. 



