1886.] THE HUME COLLECTION. 75 



and darker-roloured incisors, and longer and narrower molars. 

 From that of S. lepidus it differs by its much larger size in every way, 

 and its stouter and more powerful teeth. From both also it differs 

 by not possessing any trace of the minute first upper premolar 

 generally present in the genus, a character usually fairly constant in 

 the true Squirrels, but on which too much stress must not be laid on 

 the evidence of a single specimen only. 



Measurements (of a skin and therefore merely approximate) : — 

 Head and body 142, tail 172, hairs at end 23 ; hind foot 36 ; heel 

 to front of last foot-pad 16 ; ear (above crown) 18"5. 



8kull. Length of face ^ 23'0, greatest breadth (c) 30*0, interorbital 

 breadth 11-2, tip to tip of postorbital processes 18'0 ; nasals, length 

 ]4*1, breadth 7'0 ; diastema Mb; palate, length 23'8, length of 

 molar series 9 "5, breadth across palate outside m^ 9 '7, inside 5*1. 



This beautiful little species reminds one superficially both of 

 S. pearsoni, Gr., and -S. lepidus, Horsf., with the latter of which I 

 consider S. spadiceus, Ely., should be amalgamated. From S. pear- 

 soni it differs in its broader, naked, and untufted ears, and its longer 

 and more distinctly distichous tail, while from S. lepidus it is 

 distinguished by its larger size, much larger and broader ears, orange 

 instead of brown parachute, clear instead of slate-mixed belly, and 

 by the briUiant orange of the underside of its tail. 



S. sagitta, Linn., which Dr. Anderson was unable to identify, 

 seems to me to be unquestionably the species commonly known as 

 S. horsf eldi, Waterh., the original description agreeing in almost 

 every respect, and the locality being the same. The differences 

 between S. sagitta and ^. davisoni are too obvious to need pointing 

 out. 



It is with the greatest pleasure that I take the opportunity of 

 naming this beautiful species after my friend Mr. W. Davison, the 

 collector of the greater part of the Hume mammals, and to whose 

 powers of observation and collection, the sciences of ornithology and 

 mammalogy are so largely indebted. Mr. Davison obtained himself 

 for Mr. Hume nearly the whole of the Tenasserim and Malay 

 peninsula collections, and also the whole of the specimens from 

 Simla and from S. Lidia presented with them. 



19. SciURUS BicoLOR, Sparrm. 



a, b. Salanga, Junkcevlon, 2 and 3/79 (Darling), c. Dingding R. 



24/2/79. J-^."Klang. Ti. Malacca, 9/75. i. JaflFaria, 



Johore, 17/3/80. j-l. Gunnong Pulai, Johore, 7 & 8/79. 



With the exception of three or four of the cream-coloured 



examples so common in this species, all these specimens represent 



the typical black and yellow S. bicolor. This Squirrel has six 



mammae, all in the inguinal region. 



' From the tip of nasals to a point on the forehead above the constriction 

 between the cerebral and olfactory chambers. The " length of bi-ain-case," when 

 given, is from the same point backwards to the most postcrioi- point of the inter- 

 parietal bone. 



