1908.] MAMMALS FROM NORTHERN CHIXA. 977" 



average length and hairiness, brown above, lighter below, not 

 sharply contrasted. Mamma? — 2 = 4. 



Skull with a marked general resemblance in form to that 

 of Ar. melanogaster , having the same unusually broad intei'orbital 

 region, and smooth unridged surface with the angles and crests 

 scarcely developed, not even the oldest specimen showing any 

 trace of frontal crests. Palatal foramina medium. Posterior 

 palate more complete than in that species, the lateral grooves 

 reduced to small or minute disconnected foramina, the posterior 

 border squarely transverse, running completely across to the 

 molars ; ridges bounding mesopterygoid fossa running above 

 (dorsal to) this posterior border, and curving down to join it on 

 its dorsal aspect. Bulla? of average size. 



Teeth with the triangles tending throughout to be completely 

 closed, thus contrasting Avith those of M. melanogaster in which 

 they ai'e mostly open. M^ with the usual 5 spaces, 3 external and 3 

 internal salient angles, and m" with 4, 3 and 2 respectively, and 

 each tooth with a tendency to the development of a small extra 

 jDOstero-internal angle, very different to the large extra angle of 

 the allied form. M'' narrow, rather elongate, with five separated 

 spaces, three external and three internal salient angles, and a 

 long posterior lobe. First lower molar normally with four closed 

 triangles, and the partly open one in front of them joining the 

 anterior trefoil, but this is sometimes also closed, making a fifth 

 closed triangle. M, either wdthout closed triangles, or the middle 

 space separated into two. 



Dimensions of four specimens, measured in the flesh : — 



cT . Head and body 88 mm. ; 



; tail o\ ; 



hind foot 16 ; 



ear 10-5, 



6. „ 89 „ ; 



oo . 



„ oo , 



16 ; 



„ 11. 



2 (type) „ 90 „ : 



; .35; 



15-5; 



; „ 11. 



$. „ 88 „ : 



; „ 33: 



16 ; 



„ 11. 



Skull of type — greatest length 23'5 mm.; basilar length 20 ; 

 zygomatic breadth 15"5 ; length of nasals 6"7 ; interorbital breadth 

 4"2 ; height of crown fi-om front of alveolus of m'' 7"2 ; palatilar 

 length lO'l ; palatal foi-amina 4'1 ; length of upper mohir series 

 (crowns) 5'7. 



Hah. as above. 



Type. Adult female. R.I\r. No. 9.1.1.188. Original number 

 1892. Collected 28 May, 1908. 



This interesting little Vole would appear to be most nearly 

 allied to M. (Eothenomys) onelanogaster, but difi;ers strikingly iu 

 the closure of many of the dental triangles open in that animal. 

 Its palate is also much more complete posteriori}^, and its fore 

 instead of its hind claws ai'e slightly the longer. 



In colour Jf. inez is also unique, its peculiar pinkish-lirowii 

 colour being quite unlike that of any other Vole in the Museum 

 collection ; indeed, owing to its coloiu', it was mistaken for a 

 " Redback" by Mr. Anderson. 



" In the mountains N. W. of Ko-lan-chow, Shan-si, this Redback 



62* 



