MAMMALS COLLECTED IN SIAM. 365 
dorsal area only occasionally slightly blackened by black-tipped 
hairs; head suffused with rich ochraceous, underparts yellow ochre 
to buff (at the most only partially tinged with burnt sienna ) and 
divided mesially by a grizzled line, 
Colour. Upperparts varying from a grizzle of buff and 
black to one of ochraceous ani black slightly darkened on mid- 
back and the rump in the majority of the series; muzzle, tcp of 
head and ears varying from Mars yellow to orange buff less speck- 
led with black than the back, the brighter heads going with the 
brighter bodies; the backs of the ears paler greyish yellow, ungriz- 
zled. Hands and feet rather darker than the limbs, as dark as the 
back where blackened. 
Underpaits :—chin, throat and neck varying from yellow 
scarcely grizzled to a fine grizzle of buff and grey; a grizzled median 
line of varying breadth of the same colour as the sides of the 
body ; the areas between the grizzled -parts buff to yellow ochre, 
these colours extending less distine tly along the under sides of the 
limbs. In about 30 per cent the yellow area is suffused with burnt 
sienna, least on the chest, strongest on the axillary region and the 
thighs. 
Tail varying from buff to. ochraceous-orange annulated with 
black, the latter forming distinct bands distally except on the last 
inch or so where the hairs have long buffy or albescent tips; whis- 
kers black. ‘ . 
Those specimens which have more richly coloured underparts 
are also, on the whole, more richly coloured throughcut. 
Remarks. This is obviously a variable squirrel, though not, 
I think, a race of true individual variation, but rather one in which 
each animal goes through a cycle of change; as this change, how- 
ever, does not seem to take place at a time common to all, it cannot 
be considered sersonal. The absence of any such occurrence is 
shown by three examples taken in June*; one of them is indis- 
tinguishable from examples of the November series and the others 
only differ in having the heads duller (yellow wore ). 
» Coll. Messrs. W. J. F. Williamson and M. A. Smith. 
VOL. Ill, NO. 4, 1919. 
