Bornean Species of the Genus Mus. 459 



dirty buff, the hairs slaty grey basally, buff terminally ; line 

 of demarcation on sides not sharply defined. Ears of medium 

 size, laid forward in a spirit-specimen they almost reach the 

 anterior canthus ; thinly haired, brown or black. Metapodials 

 brown mesially, whitish laterally and on the digits ; fifth hind 

 toe reaching to the end of the first phalanx of the fourth. 

 Tail rather longer than head and body, unicolor, dark brown, 

 fairly well haired, but not tufted. Palate-ridges 3 — 5, the 

 three anterior interdental, as usual in this and the ephippium 

 group, with a sharp backwardly-directed projection in the 

 centre. Mamma 2 — 3 = 10. 



Skull distinguished from that of M. negleclus by its much 

 broader and rounder brain-case, on which the parietal ridges 

 are more widely bowed outwards, by its broader and shorter 

 interparietal, and by its less widely open anteorbital foramina, 

 of which the outer walls are less projected forwards. 

 Hind foot of the typical skin 33'5 millim. 

 Dimensions of a spirit-specimen ( $ ) : — 

 Head and body 171 millim.; tail 19-4; hind foot 32; ear 

 20x17. 



Skull : see below. 



Hab. Mount Kina Balu, 8000 feet. Coll. J. Whitehead, 

 Feb. 4, 1888. 



The specimens referred to as being soft-haired examples of 

 Mus rattus in my original paper on Mr. Whitehead's mammals, 

 together with two spirit-specimens sent by Mr. Everett, are 

 those on which Mus baluensis is now founded. What its 

 ultimate position will be, when all the group is worked out 

 with proper material, I am unable to say ; but I a in convinced 

 that, as a local form, whether species or subspecies, it is 

 quite distinct from anything hitherto described. 



Skull-measurements of the Neio Species above described. 



ochracei- White- balu- 



rajah. venter, headi. bceodon. ensis. 



r? rT . r7 9 <-? 



Greatest length (c.) 51 40 33-6 32* 43-2 



Basilar length to henselion (c.)41 30"5 25*4 25 35 



Greatest breadth 22 13 16 15 20-4 



Nasals, length 19 15 11-4 12 15-5 



Interorbital breadth .... 7'5 7'6 6-1 6 6-8 



Interparietal, length 5-8 5-8 5'0 6 5-9 



„ breadth.... 10 10-4 9-0 9-2 12-5 

 Length of zygomatic plate 4-2 2*9 3-2 2-3 4-5 

 Palate length from hen- 

 selion 22 16-2 13-6 12 21-3 



Diastema 14-6 11-2 8-9 8-9 12-6 



32* 



