356 MR. C. BODEN KLOSS ON 
Two young animals are as brightly coloured above as the 
alults but ars much less speckled with black, below they are yellow- 
ish slightly tinged with burnt sienna except for the neck and 
median line. 
Type. Adult male (skin and skull) No, 2395/C.B.K. Col- 
leeted at Koh Lak, S. W. Siam on 9th November, 1916. 
(For measurements see table postea.). 
25. Sciurus atrodorsalis tachin. 
Kloss, Journ Nat, Hist. Soc. Siam. ii, p. 178 (1916.) 
93 ad. 62 ad. 12 imm. Pak Bu, Tachin, Central Siam. 
A form of Sciwrus atrodorsalis Gray, remarkable for small] 
size and rare development of a black dorsal patch. 
Above a grizzle of black and yellow, the latter ranging 
from antimony yellow to cream, but the general colour effect very 
variable owing to the very variable amount of black speckling. 
Muzzle rather brighter than the back and less blackened; limbs 
grey and duller. 
In rather less than half the series there is a slight darkening 
of mid-back and rump, owing to the presence of more distinctly 
black-tipped hairs, and in one specimen this darkening takes the 
form of an elongate black patch, though only the tips of the hairs 
are blackened, 
Ears generally tawny, sometimes a tawny ring round the 
eye and the muzzle tinged with the same colour; backs of ears 
buffy-grey. Hands and feet generally, though not always, darker 
than the limbs. 
Chin, throat and chest a grizzle of buffand grey which 
extends backwards as a median line broadest on the chest; rest of 
underside of body with limbs varying from burnt sienna throughout, 
or zine orange, or bright yellow-ochre sutfused with ferruginous on 
the thighs. In three or four examples the yellow is much reduced 
and very faint. 
Tail usually black and faint buff forming bands distally, most 
distinct towards the tip which is generally albescent. In the 
immature animal the annulations are obseured by a wash of 
JOURN, NAT, HIST. SOC, SIAM. 
