278 SMITHSONIAN MISCELLANEOUS COLLECTIONS [voL. 48 
Tarussan Bay which are quite different from specimens collected 
along the low east coast of the island. The latter cannot be dis- 
tinguished from Sciurus peninsularis Miller.t Until a good series of 
specimens is collected at Bencoolen the status of Sciurus vittatus 
Raffles and of Sciurus peninsularis Miller, must remain unsatisfac- 
tory. In this paper I use these two names as synonymous. 
The differences in color of the different forms do not appear 
to be dependent upon season, but it is much to be regretted that 
material collected at all seasons is not available from each type 
locality. The east coast series, collected from March to September, 
is quite uniform and the relatively slight variations are individual 
and not seasonal. Two of the most differently colored forms 
(from Tarussan Bay and Tapanuli Bay) differ only a month as to 
season in which collected and are nearest geographically. 
It is probable that the four forms here recognized are true sub- 
species of Sciurus vittatus and that if specimens were available from 
intermediate localities complete intergradation of one form to another 
would be found. As it is, the forms described below are quite dis- 
tinct and the individual variation in any series is hardly great enough 
to connect one variety with another. Once the characters of the 
different forms are known, each of the thirty-four skins of squirrels 
of this group collected by Dr. Abbott in Sumatra can, without refer- 
ence to the labels, be referred to one of the four different subspecies 
here described. 
Apparently there are no characters in the skull by which the 
different subspecies may be distinguished from each other, except 
the slightly smaller size in the northern race. 
KEY TO THE SUMATRAN SQUIRRELS OF THE SCIURUS VITTATUS GROUP 
A. Pelage with scattered white hairs on underparts. 
Sciurus vittatus albescens, 
A’. Pelage without scattered white hairs on underparts. 
C. Underparts lighter, deep ochraceous-buff...Sciurus vittatus tarussanus. 
C’. Underparts darker, deep orange-rufous to ferruginous. 
D. Upper surfaces of feet dull tawny or ochraceous, and black lateral 
stripe more distinct and clear........ Sciurus vittatus vittatus. 
D’. Upper surfaces of feet inclining to grayish, not tawny or och- 
raceous; black lateral stripe less clear and distinct. 
Sciurus vittatus tapanulius. 
SCIURUS VITTATUS VITTATUS Raffles 
1822. Sciurus vittatus RAFFLES, Trans. Linnean Soc. London, x11, p. 259. 
1Smithsonian Miscell. Coll., xtv, No. 1420, November 6, 1903, p. I0. 
