Mr. O. Thomas on a neio Rat from North Borneo. 269 



XXXI. — Description of a new Rat from North Borneo. 

 Bj Oldfield Thomas. 



Among the small Mammals obtained by Mr. John White- 

 head during his expedition to Mount Kina-Balu is a skin of 

 a very handsome long-tailed rat belonging to the group of 

 mountain-rats that contains Mus Jerdoni^ BL, M. Edwardsi, 

 Thos., M. coxinga, Swinh., M. Bianfordi, Thos., M. Hell- 

 waldij Jent., and others, but representing a new and very 

 distinct species. I propose to call it 



Mus sabanus *, sp. n. 



Fur short and fine, mixed with slender spines along the 

 centre of the back. General colour rufous, mixed with brown 

 along the top of the head and back, brighter and clearer 

 on the cheeks and sides, the general tone very similar to that 

 of M. Jerdoni. Whole of underside pure creamy white, 

 sharply defined from the rufous of the sides. Outsides of 

 limbs like sides, but rather greyer, inner sides white ; lower leg 

 and ankles greyish brown all round. Hands and feet brown 

 along the middle of their upper surfaces, their edges white, 

 the contrast especially strongly marked on the feet, where a 

 broad band of deep blackish brown passes along the centre, 

 edged on each side with pure white. Sole-pads large, smooth 

 and prominent, the last one about three times as long as 

 broad. Fifth hind toe, without claw, reaching to the end of 

 the first phalanx of the fourth. Ears rounded, rather short, 

 laid forward they do not reach to the eyes. Tail enormously 

 long, evenly finely haired, the scales, which are large, 

 averaging from seven to nine to the centimetre, uniformly 

 dark brown or black above and below throughout, but the 

 hairs black for the proximal two thirds above only, elsewhere 

 pure white. 



Dimensions of the type, an adult male, preserved as a 

 skin : — 



Head and body 280 millim. ; tail 340 ; hind foot 43*5 ; ear, 

 above head 18, breadth 18 ; heel to front of last foot-pad 23 ; 

 length of last foot-pad 7*0. 



8kull : tip of nasals to centre of fronto-parietal suture 36 

 millim.; nasals, length 21, greatest breadth 6'0 ; interorbital 

 breadth 7*7; anterior zygoma- root, length 4*7 ; palate, length 



* From Saba, the district of North Borneo in which Mount Kina-Balu 

 stands. 



Ann. & Mag. N. Hist. Ser. 5. Vol. xx. 19 



