498 Squirrels of the Ratufa (Sciurus) bicolor Group. 



surface being uniformly annulated. The present species is of 

 a light chocolate-brown above (" Prout's brown " of Ridgway, 

 as it is styled in the original description). Underparts deep 

 ferruginous ; feet black. 



Dimensions (from skin) : — 



Head and body 350 millim. ; tail 420; hind foot 63. 



Skull : greatest length 63 ; basal length 50 ; zygomatic 

 breadth 39 ; greatest length of nasals 19'4 ; length of palate 

 to henselion 27"5. 



Ilah. Island of Bunguran, Natuna Group. 



This species, in common with the two succeeding forms, 

 bleaches to a great extent^ giving rise to many varieties. 



Ratufa ephippium nanogigas (Thos. & Hart). 



Sciurus ephippium nanoyigus, Thos. & Hart, Nov. Zool. ii., Dec. 1895, 

 p. 491. 



Resembles R. eph.. hungurancnsis very closely except as 

 regards size. The underparts also are much lighter in colour, 

 being light yellow. 



Dimensions (from skin) : — 



Head and body 330 millim. ; tail 347 ; hind foot 60. 



Skull : greatest length 47'5 millim. ; basal length 43 ; 

 zygomatic breadth 34 ; greatest length of nasals 16 ; length 

 of palate from henselion 21. 



Ilah. Pulau Laut, N. Natunas. 



Ratufa ephippium sirhassenensis, subsp. n. 



Sciurus ephijopium albiceps, Thos. & Hart, Nov. Zool. i., Sept. 1894, 

 p. 659. 



Allied to the hunguranensis-nanogicjas group and inter- 

 mediate in size between the two. In the general coloration it 

 resembles the smaller of the two {nanogigas)^ but differs 

 from that species in the light annulations to the hairs being 

 broader and lighter, while the ears, sides of the face, and 

 outer sides of the limbs are of the same colour as the under- 

 parts, viz. light yellow, instead of black, as in nanogigas. 



Dimensions (trom skin) : — 



Head and body 340 millim. ; tail 410 ; hind foot 60. 



Skull : zygomatic breadth 37 ; greatest length of nasals 18 ; 

 length of palate from henselion 23'5. 



}lab. Sirhassen Island, Natuna Group. 



Ty^e B.M. 94. 9. 28. 13. Sirhassen, 23rd Sept., 1893. 

 Collected by Mr. A. Everett. 



