new Rodents from Kan-sii. 721 



median sagittal crest, small teeth, au'.l two rc-cntiant angles 

 on m^. 



t>ize ratlier less than in M. fontanieri. Colour dark 

 (habby, the belly little lighter; crown blackened in the 

 type. Hands and feet whitish, well-haired, but the hairy 

 part terminating at the bases of the digits, the skin covering 

 the bases of the claws naked. Tail pro[)ortionally rather 

 short, dull greyish white. 



Skull with the essential characters of the fontanieri-cansus 

 grouj), in which the occipital region forms a ridged and 

 projecting hump behind the transverse masseteric crests. 

 Kasals about equalling the premaxillae posteriorly. Inter- 

 orbital region narrow, its edges, even anteriorly, rounded, 

 not ridged as in all the other species of the group. Masse- 

 teric fossffi of the two sides with their inner ridges closely 

 aj)j)roximated, separated by a groove scarcely half a milli- 

 metre in breadth, and therefore practically forming a median 

 sagittal crest. Transverse crest not immensely developed, 

 and, as usual in this group, obsolete in the centre. Lateral 

 crests on occipital hump well developed, but no median 

 occipital crest present. 



JVloIars small in proportion to the size of the skull, their 

 structure as in M. cansus, except that there is a weil-marked 

 second re-entrant angle on the inner side of m'. 



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



Head and body 202 mm. ; tail 41 ; hind foot i-^2. 



Skull : greatest (condylo-nasal) length 50'3 ; condylo- 

 iiicisive length 46*2 ; zygomatic breadth i34'6 ; nasals 18'6 ; 

 interorbital breadth 7*3 ; breadth on transverse crest 30'4 ; 

 palatilar length 22*8; palatal foramina 8'3; upper molar 

 series (crowns) 10*2, (alveoli) 10*6. 



Uab. (of type). 30 miles S.E. of Tao-chou, Kan-su. 

 10,000'. A specimen from Gumansa, Kan-su, collected by 

 G. Grzimailo and received from the St. Petersburg Museum in 

 1892, is believed to be of the same species, but the diagnostic 

 parts of the skull are broken away. 



Ti/pe. Adult male. B.M. no. 11. 11. 1. 1. Original 

 number 172. Collected 6th April, 1911, by Dr. J. A. C. 

 Smith and presented by the Hon. N. Charles Hothschild. 



The close approach of the two masseteric fo3sa3 to each 

 other in the middle line is a character quite unique in the 

 genus. The rounded supraorbital margins, small teeth, and 

 the two re-entrant angles on the iinier side of m^ also seem to 

 distinguish this species from its allies. 



