80 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.40. 



specimens from the lower Kapuas, and some from the Sempang and 

 Semendang rivers, with darker underparts and "reddish" shoulders. 

 3. The Kendawangan River specimens with lighter underparts and 

 shoulders, and a clearer white on the thighs. In any of the three 

 o-roups a few intergrading specimens may be found. As none of the 

 three forms has a definite range, so far as known, it does not seem 

 advisable to recognize them by name. The characters of the Ken- 

 dawangan River series, however, are nearly as distinctive as are those 

 of some of the insular forms of the prevostii group of squirrels. 



(For measurements, see table, p. 83.) 



See figure next to the bottom one on plate 4. 



SCIURUS ATRICAPILLUS Schlegel. 



1863. Sciurus atricapillus Schlegel, Nederl. Tijdschr. Dierk., vol. 1, 1863, p. 27; 

 Zoogdieren, pi. 2, fig. 1. 



Doctor Abbott collected one squirrel of the Sciurus prevostii group 

 at Balik Papan Bay, which is referable to S. atricapillus. 



Mr. Miller has made the following notes on the original material of 

 this species in the Leyden Museum : 



Sciurus atricapillus. — Seven mounted specimens from Borneo — four from Kapuas 

 River, one from Duson River, one from southeastern Borneo, and one from Borneo — 

 also one skin from Liang Koeboeng, back of Pontianak. They are very uniform, and 

 agree perfectly with a specimen of this species in Berlin. In two of the Kapuas 

 specimens the hairs of the tail are clear black throughout except for the narrow light 

 base; in the third adult a few light annulations can be detected; in the immature 

 individual there is conspicuous annulation beneath the surface. This is also present 

 in the four others to a variable extent, but never appearing distinctly at the surface 

 unless the hairs are disarranged. Muzzle always black, usually to a little behind 

 eyes; feet always black; red area, dark rufous, shading toward chestnut; pale side 

 stripe cream color, 10 mm. wide; dark stripe about same width; cheeks grizzled buffy 

 brown. 



Doctor Abbott's specimen agrees in every way with the above 

 description, as well as with the original account. The type-locality 

 may be taken as the Kapuas River, 4° or about 270 miles east of Pon- 

 tianak, as that locality is the first mentioned in the description and 

 the majority of the specimens came from there. The species is seen to 

 have quite an extensive range — from the center of the island to the 

 southeast coast, at least. Sciurus atricapillus probably intergrades 

 with S. caroli 1 and its subspecies in northern Borneo. 



It resembles S. caroli griseicauda in general external appearance 

 more than any other member of the group that I have seen. The 

 black color of the tail, of the nose, and adjacent parts of head, includ- 

 ing an ill-defined ring about the eye, and the black feet of S. atrica- 

 pillus serve to distinguish the two forms. 



(For measurements, see table, p. 83.) 



See bottom figure on plate 4. 



' Bonhote, Ann. Mag. Nat Hist., ser. 7, vol. 7, February, 1901, p. 174. 



