28 SMITHSONIAN MISCELLANEOUS COLLECTIONS [VOI,. 50 



Skull. — Besides its smaller size, the skull of Sciurus hippurellus is 

 distinguished by its heavier rostrum, broad expanse of the premax- 

 illae on its upper surface, and more slender zygomata. (Fig. 12, 0.) 



Measurements. — See table, page 29. 



Specimens examined. — Three — two from the L,andak River and 

 one from the Kapuas River, below Tyan, western Borneo. 



Remarks. — This species is quite closely related to the squirrels 

 from Sumatra and the Malay Peninsula and very different in point 

 of coloration from the race inhabiting northern Borneo. 



SCIURUS GRAYI Bonhote 



1S67. Macroxus rufogaster var. Borneensis Gray, Ann. Mag. Nat. Hist., 

 3d ser. , xx, 1867, p. 283 — not Sciurus borneoensis (Miiller and 

 Schlegel), 1839-44. 



1901. Sciuius hippurus Grayi Bonhote, Ann. Mag. Nat. Hist., 7th ser., 

 vn, February, 1901, p. 171, foot-note. 



Diagnostic characters. — A member of the Sciurus hippurus group, 

 with the color of middle line of the back very dissimilar to the sides, 

 closely resembling burnt sienna, sparsely grizzled with black. 



Color. — This species differs in color from Sciurus hippurus de- 

 scribed above as follows : The color of the sides is found on the 

 top of the head as far forward as the eyes, instead of to the ears 

 only ; the mid-dorsal area for a width of 30-40 mm., beginning at 

 the base of the neck and extending on base of the tail above, differs 

 in color from the sides, being like Ridgway's burnt sienna, spar- 

 ingly grizzled with black ; the grizzle of the upper neck and sides 

 consists of black and tawny, instead of black and raw sienna ; the 

 black of the tail has more of a brownish cast ; the underparts are 

 dark as they are in the squirrel from the Malay Peninsula ; the outer 

 side of the forearm is gray, as in the Sumatran and peninsular forms, 

 and not concolor with the sides, as in the other Bornean species. 



Skull. — The skull of Sciurus grayi closely resembles that of Sciurus 

 hippurellus. 



Measurements. — See table, page 29. 



Specimens examined. — Six, from northern Borneo. 



Remarks. — This species is very distinct from the other known 

 members of this group and shows more differences from the west 

 Borneo form than the latter does from Sumatran and Malay Peninsula 

 forms. 



