76 MILLER 



ventral surface of tail seal brown. Bleached pelage not known. In 

 the type and one or two other specimens the last remnants are still 

 visible in the form of some irregular patches of hair in the tail much 

 lighter than that of the surrounding parts. 



Skull. — Skull nearly equal to that of Rahifa melanopepla in size, 

 but in form of nasal bones agreeing with that of R. ajffinis. Ptery- 

 goids long, the length of interpterygoid fossa much more than twice 

 the breadth. 



Teeth. — While the teeth show no marked peculiarities in form they 

 are actually as well as relatively smaller than in Ratufa affinis and 

 R. incla?topepla, and the upper premolar is narrower. 



J\Ieasuremcnts. — External measurements of type : total length 

 756 ; head and body 356, tail vertebrae 400 ; pencil So ; hind foot 85 

 (77)' Average of seven specimens from the type locality: total 

 length 749 (717-775) ; head and body 341 (330-356) ; tail vertebrae 

 408 (400-432); hind foot 81.4 (75-85); hind foot without claws 

 72.5 (69-77). 



Cranial measurements of type : greatest length 65 ; basal length 55 ; 

 basilar length 51 ; palatal length 25.4; length of nasals 21 ; breadth 

 of nasals anteriorly 12; breadth of nasals posteriorly 11.4; least 

 breadth of nasals 8 ; interorbital breadth 26 ; breadth between tips of 

 postorbital processes 38.6; zygomatic breadth 41; mastoid breadth 

 31; breadth of palate between premolars 10; depth of rostrum at 

 posterior extremity of nasals 17.4; mandible 37; depth of mandible 

 at posterior root of premolar 9.8 ; least depth of mandible between in- 

 cisor and premolar 6.4; maxillary toothrow (alveoli) 13; breadth 

 across both upper incisors at rim of alveoli 7 ; mandibular toothrow 

 (alveoli) 1 1.6. 



Specimens examined. — Seven, all from the type locality. 



Rc7narks. — Ratufa pyrsonota differs so widely from R. a/fiiiis in 

 both size and details of color that no close comparison between the two 

 species is required. The line speckling of the upperparts, due to tlie 

 minute pale subterminal bands of the longer hairs, is alone suilicient 

 to distinguish the northern animal. Another noticeable character is 

 the color of the feet. This is much darker than the leg in Ratufa 

 pyrsofiota^ and conspicuously lighter than the leg in R. affuiis. From 

 Ratufa vicla)iopcpla this species is readily separable by its smaller 

 teeth and differently shaped nasal bones, aside from the totally dif- 

 ferent color. Even bleached specimens of the black-backed animal 

 show only the most superficial likness to R. pyrso)iota., a similarity 

 that at once disappears when the details of coloration are examined. 



