] ^oles fro m Yu iinau. 1 5 7 



Like irene, Ijut much larger. 



Geueral appearance closely resembling irene, but size 

 much larger, the head aud body in adults averaging 120 

 instead of about 92 mm. Tail, feet, and ears relatively 

 shorter, averaging respectively about 30, 16, and 12 per 

 cent, of the head and body measurements in adults, instead 

 of about 40, 19, and 11 {)cr cent, as in adult irene. Fur soft 

 and fine, longer than in ireyie ; hairs of back about 15 mm. 

 in length, instead of al)out 9 as in irene (measured in both 

 cases upon specimens collected in July). 



General colour of upper surface dark brown (near 

 *' mummy-brown" of Ridgway) ; of underparts slaty, Avashed 

 with greyish white. Ears concolorous wdtli back. Hands 

 and feet greyish white ; soles with six pads. Tail fully 

 haired, more or less distinctly bicoloured, brownish to 

 dusky above, dirty white on sides and below. Mammse 

 2—2 = 8. 



Skull, apart from its conspicuously large size, not essen- 

 tially very different from that of irene. Brain-case rather 

 longer and narrower. Postorbital squamosal processes and 

 temporal crests, including the interorbital sagittal crest, 

 sharply defined in fully adult stages. The skulls of the 

 immature examples before me equal those of adult irene 

 in size, but are distinguished from the latter by lacking all 

 trace of the crests and ridges develojied in the adults of 

 both species. 



Cheek-teeth simpler than in sikimensis, but slightly less 

 reduced than in irene : m^ and m- without vestiges of 

 cusp n ; fourth outer and fourth inner angles of m^ vestigial 

 or obsolete; 7?^^ with the three closed, triangles followed by 

 one transversely confluent pair and terminated by an anterior 

 loop of nivaloid form; jn^ normal; m^ with third outer 

 angle obsolete. 



Dimensions of the type, measured in the flesh: — Head and 

 body 134 mm.; tail 43; hind foot 19; ear 14. 

 '^ For skull-measurements, see table at p. 159. 



Type. Adult mcile. B.M. No. 22.12.1.35. OriginalNo. 145. 

 Collected July 6, 1921, by Mr. G. Forrest, upon the divide 

 between the Mekong and Yangtze Rivers, N.W. Yunnan, in 

 latitude 27° 30' N. Altitude 11,000' to 12,000'. 



Mr. Forrest is to be congratulated upon the discovery of 

 this flne vole, which 1 have pleasure in associating- with his 

 name. N. Jorresti is of considerable importance, as the 

 Imk connecting Hodgson's sikimensis with the three much 

 smaller, and at first sight very dissimilar, species described 

 more recentlv bv Thomas. 



