84 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.40. 



Skull and teeth. — These show no striking peculiarities, but the 

 audital bullae are distinctly more inflated than they are in the closely 

 related Sciurus carimatse, especially noticeable in the anterior segment 

 of the bullae. 



Measurements. — For external and cranial measurements of the type 

 and series, see table on p. 83. S. pelapius is one of the smaller mem- 

 bers of the prevostii group, about the same size as S. carimatse. 



Specimens examined. — Three, all from South Island, Pelapis. 



Remarks. — Sciurus pelapius is very closely related to the near-by 

 S. carimatse, the only distinguishing characters being its darker and 

 "redder" shoulder and larger audital bullae. Two specimens in the 

 carimatse series have shoulders nearly as dark as those of pelapius, 

 but none that I have seen shows the more inflated bullae. 



SCIURUS DULITENSIS (Bonhote). 



1901. Sciurus vittatus dulitensis Bonhote, Ann. Mag. Nat. Hist., 8er. 7, vol. 7, 



p. 451, May, 1901. 

 1907. Sciurus dulitensis, Lyon, Proc. U. S. Nat. Mus., vol. 33, No. 1577, p. 555, 



December 24, 1907. (Kapuas River region.) 



Since he collected nine specimens of plantain squirrels from the 

 Kapuas River region Dr. W. L. Abbott has secured eleven additional 

 specimens in southwestern Borneo, eight in southeastern Borneo, and 

 one on Pulo Laut. As far as the general coloration of the upper 

 parts and side stripes is concerned all the Bornean specimens are 

 fairly constant. They vary considerably, however, as to the bright- 

 ness of the under parts, as may be seen even in specimens from one 

 locality. The single specimen from Pulo Laut does not seem to be 

 separable from the others. 



It is noteworthy that nearly all the specimens from the Kapuas River 

 region, as well as several in the U. S. National Museum from northern 

 Borneo, have the entire under side of the tails distinctly reddish or 

 rufous, while nearly all the others from Borneo have the entire under 

 side of the tail generally grayish. This character is not absolutely 

 constant and at best could only be considered a subspecific one. The 

 difference can not be attributed to season, sex, or age. Without 

 more specimens, especially well-prepared skins from northern Borneo, 

 it does not for the present seem advisable to recognize this difference 

 by name. 



It may not be without interest to point out how easily the "red" 

 color of the underparts of the Sciurus vittatus group of squirrels may 

 become altered. There are in the museum two specimens of Sciurus 

 dulitensis from north Borneo, collected by C. F. Adams in 1887. At 

 that time they were preserved by some pickling solution, probably 

 salt and alum. The underparts are now a dull vinaceous-cinnamon, 

 instead of the usual bright ochraceous colors. Some other specimens 



