2 Proceedings of the Biological Society of Washington. 



cream-colored or whitish; cheeks, chin, sides of neck and front of breast 

 dull mouse gray; ears dusky; feet brownish black; tail in proximal third 

 wood brown slightly, or not at all, tipped with black on under side and 

 rather broadly tipped with it, at least medially, on upper side; tail in 

 distal two-thirds brownish black, the hairs more or less brownish fawn 

 at their bases. 



Skull and teeth. — Skull similar in general to that of Sciuropterus 

 nigripes, but smaller; nasals rather contracted posteriorly and definitely 

 exceeding premaxillae; interparietal with transverse dimension exceeding 

 longitudinal; fronto-parietal suture acutely emarginate; front edge of 

 coronoid process unbeaded ; incisor teeth decidedly more slender than in 

 S. nigripes ; cheekteeth essentially as in nigripes, but nearly ten per cent 

 smaller. 



Measurements. — Total length, 500; tail, 250; hind foot, 45; ear, 25. 

 Skull of type: Occipito-nasal length, 45.7; basal length, 42.5; zygomatic 

 breadth, 28; length of nasals, 14.5; anterior breadth of nasals, 8.1; pos- 

 terior (least) breadth of nasals, 3.6; length of palate, 21.5; diastema, 

 8.8; upper cheekteeth, 10.S; length of large premolar, 2.5. 



Remarks. — The obvious derivation of the above-described form from 

 S. nigripes seems to warrant its association with that species as a race. 

 Of the two specimens examined, both have the teeth practically unworn 

 and therefore may not represent the maximum size, but comparison has 

 been made with specimens of nigripes of corresponding and less advanced 

 stages of maturity. Aside from the present form and S. nigripes, the 

 only other flying squirrel known from the Philippine Islands is Sciurop- 

 terus crinitus Hollister, which is from Basilan Island and is referred to a 

 different subgenus. 



