the Celebes. The moustachial and cheek bristles are greyish, the cheeks being
black, but finely grizzled with grey, a colour which does not occur in 8. rufoniger.
The type of 8. rufoniger is black above, with a greyish tinge on the shoulder and
outside of the thighs, and along the sides, in which latter locality this colour is distributed
in a linear form, but in some Bornean examples the grey assumes the
character of a white band between the axilla and groin, the grey being absent on
the shoulder and thighs, while in others from the same locality, the white or grey
is almost obsolete, being reduced to an obscure lateral line, while in another specimen
there is no trace of it beyond a few greyish hairs along the position occupied
by the lateral line in the others, and in this respectxit resembles S. erythromelas.
The grey or white lateral line is always separated from the deep chestnut of the
under parts by an intense, but narrow black line. The chin, and all the upper parts
and the outside of the limbs and the tail, are jet black. The throat and all the
under parts are deep chestnut.
8. schlegelii is from Koma, also in the Celebes. The fur is wholly and finely, but
sparsely grizzled with yellow on the upper parts and on the tail and on the outside
of the limbs, but the feet are black. The sides of the face around the eye are rich
chestnut, passing into deep maroon on the under parts. There is a pale yellowish-
grey line from the shoulder to the groin, and below it a black band. The tail is
black, sparsely grizzled with yellow, and terminating in a black tip.
All of these forms lead so gradually from one into the other that their specific
identity seems unquestionable. The series here considered, yields indisputable evidence
that the white or grey lateral streak occasionally disappears by the white
being replaced by black hairs, but it is found in every stage of disappearance, and in
some it is only indicated by the intermixture of a few white among the black
hairs. Likewise, the underlying black streak is also the subject of analogous changes
in those forms referable to S. prevostii, var. borneoensis, the black being replaced
by the red of the under parts. The thighs and shoulders of the type of S. rufoniger
from Borneo, which is essentially the same as S. prevostii, var. borneoensis, arc also
distinctly greyish, as in the forms referred to 8. erythromelas, 8. schlegelii, and
S. atricapill/us, all of which have the white lateral streak and a distribution of
colour which baa a well-defined general correspondence throughout them all.
The next modification is one which only differs from 8. prevostii, var. borneoensis,
Schl., by the absence of the white on the moustachial region, and in the complete
disappearance of the black below the white lateral line, which is well marked in
Schlegel’s specimen. This example differs from the two first-described specimens in
the upper surface of the head, neck, and shoulders being ungrizzled jet bláck. The
sides of the face from the muzzle to the ear, and the sides of the neck, axe greyish,
more or less marked with rufous. The' shoulder is reddish, paling upwards into
yellowish, which is more or less continuous from behind with the white lateral line
which extends backwards from the shoulder to the groin; the outside of the thighs
and the legs to the ankle being grey. The fore limb is rufous, and more so than
the shoulder, but it shows the remains, as it were, of grizzling, and the hind
foot does thé same, but mtich more distinctly, being decidedly greyish-black
and rufous-grizzled, and is evidently in a transitional stage between the black
feet of 8. schlegelii and the bright red feet of what appears to me to be the
fully mature animal S. prevostii, var. borneoensis, Or 8. sawaraJcensis. The under
surface of this animal is even more lightly chestnut-red than in the previous
specimens, and the annulation of the tail has disappeared, but it is here and there
washed with greyish. Two other specimens, one of them referred by Dr. Gray
to his 8. rufogularis, are states of the pelage intermediate between S. schtegelü
and S. erythromelas, and have the upper surface of the head, neck,- and the back
and sides, with the exception of the outside of the thighs, jet black, without any
grizzling. The sides of the face and neck, the shoulder, the fore limbs and lower
half of the hind limbs, and all the under parts, are bright chestnut. There is
a white line from the shoulder to the groin, becoming grey on the Outside of the
thighs. The chin is black in One, and on it there is a faint trace Of a black lateral
line, but these black marks are absent in the other. The tail in both is black,
washed with greyish, the tip in the squirrel with the black chin being wholly black.
The red of the shoulder passes into yellowish above.
Another variety has the upper surface of the head and the middle line of the
neck and above the shoulders, and the area between the shoulder and the groin, and a
narrow space over the lumbar region jet black, also the tail, which is slightly washed
with yellowish. The sides of the face and neck, the shoulder and fore limb, and the
hind feet and all the under parts, are bright red. The upper portion of the Shoulder
passes into yellowish, and is more or less continuous with the lateral line which has
a distinct, yellowish tinge and expands on the outside of the thigh, which is clear
yellow, passing into rufous on the lower part of the leg. The black lateral line is
obsolete. In all these squirrels the base of the tail, below and around the vent,
remains greyish.
The squirrels from Borneo and the Celebes lead so perfectly from one into the
other and into the brightlÿ-inarked adult, the 8. sarawakensis, Gray, that it seems
clear they are all, as I have already said, only phases of on® species.
Apart altogether from local races, it would appear that, in the young stage,
the pelage Of this type of squirrel is grey ; that this gradually changes into black on,
the back ; that the rufous of the under parts extends by degrees, more or less,
on to the limbs, and spreads upwards on to the sides of the faee and neck; and
lastly, that the white lateral line and the grey of the thigh change into yéllow, and
occasionally the upper surface of the shoulder into yellowish-red, whilst the black
lateral line, whioh is well developed in the grey stage, disappears in the adult.
ScruRus ( E h in o s c iu r u s ) t u p a o id e s , Gray.
m inom w rw twpaoidet, Gray, List M u m B. M. 1818, p. 195 ; Ann. and Mag. Nat. Hist. 1887,
vol. XX. p. 286; Blyth, Journ. As. Soo. Beng. vol. xx. 1851, p. 167, et 1855, vol. xxiv p 477 ■
Cat. Mamm. As. Soo. Mas. 1868, p. 108.