2 2 SMITHSONIAN MISCELLANEOUS COLLECTIONS [vOL. 45 



and body, 230 ; tail vertebrae, 207 ; hind foot, 50 (47) ; skull, greatest 

 length, 54.6; zygomatic breadth, 31. 



Specimens cxaniined. — Five, all from High Island. 



SCIURUS RUBECULUS sp. nov. 



Type. — Adult male (skin and skull), No. d>6,yyy, United States 

 National Museum. Collected at Khow Sai Dow, Trong, Lower 

 Siam, altitude 1000 feet, February 21, 1899, ^J Dr. W. L. Abbott. 



Characters. — Similar to Sciurus atrodorsalis Gray, but much 

 larger. No black-backed phase at present known. 



Color. — Type : upperparts a clear fine grizzle of black and ochra- 

 ceous, the latter somewhat in excess. On sides, legs, cheeks, throat, 

 and along median line from chest to base of tail the ochraceous 

 element of the grizzle is lighter and duller than on the back, ap- 

 proaching the ochraceous-buff of Ridgway. Underparts (except the 

 grizzled area) and inner side of legs nearly to feet, bright orange- 

 rufous, darker and more red than that of Ridgway. The red area 

 is completely divided by the grizzled median line. This is about 10 

 mm. in width. Ears like back. Front feet concolor with legs, 

 hind feet slightly darker. Whiskers black. Tail like back but more 

 coarsely grizzled. On terminal half and pencil the tail is fringed 

 with clear orange-rufous due to a subterminal annulation of this 

 color on each hair. The extreme tips of the hairs forming the 

 fringe are for the most part black, but this color is easily overlooked. 

 On terminal third of tail there is a slight tendency toward the forma- 

 tion of black cross-bars, and on under side through same region 

 two faint black bands may be traced parallel with edge. 



Skull and teeth. — As compared with a skull of Sciurus atrodorsalis 

 from Kokareet, Tenasserim, that of 6". ruheculus is immediately 

 distinguishable by its greater size, and by the relatively shorter 

 broader rostrum. The audital bullae on the other hand scarcely ex- 

 ceed those of the smaller animal in size, while in form they are 

 less inflated. Frontals nearly flat anteriorly, not distinctly concave 

 as in the allied form. Teeth as in Sciurus atrodorsalis. 



Measurements. — Measurements of type : total length, 440 ; head 

 and body, 230; tail, 210; hind foot, 51 (48) ; skull, greatest length, 

 55 (50) f basal length, 49 (42) ; zygomatic breadth, 33 (29.6) ; 

 least interorbital breadth, 20.4 (17) ; median length of nasals, 14.8 

 (14.6) ; greatest breadth of both nasals together, 8 (7). 



Specimens examined. — Five, from the following localities : Trong,. 

 one, the type; Tenasserim, Bok Pyin, 3, Sungei Balik, i. 



' Cranial measurements in parenthesis are those of an adult female Sciurus 

 atrodorsalis from Kokareet, Tenasserim (No. i^ff^). 



