EXTERNAL APPEARANCE. Ant 
the buff hairs become more numerous, so that on the sides of the body and on 
the forearm they produce a clear buff or cream buff. This color of the sides 
extends ventrally from the abdominal region to the upper part of the chest 
where it passes into a deep ferruginous, almost chestnut, over the ventral surface 
of the throat, upper chest, bases of the fore limbs and dorsally to the sides of the 
neck. The inguinal region also is ferruginous. The short hairs of the feet and 
distal portion of the snout are of the same buffy color as the venter, with a 
slight admixture of ferruginous hairs around the mouth. A whitish nuchal 
spot, about 15 by 10 mm. in extent, is present in all but one of the specimens, 
and seems to be a characteristic of the species. The presence of a white nuchal 
spot is due to the failure to meet of the two lateral pigment areas whose centers 
are on the sides of the neck, as has been elsewhere indicated by the writer. The 
condition of partial albinism thus produced has here become fairly permanent, 
so as to result in a definite pattern. A similar restriction of the dermal pigment 
of the tail has taken place, so that a varying length, usually nearly the distal half, 
is white. 
Variations from the type of coloration above described occur through an 
increase or a decrease in the intensity of the pigment. One female shows a 
maximum of increase in the black of the dorsum. This color is deep on the head 
and extends to the elbows on each side, while on the back the admixture of 
buffy hairs is very slight until well down on the sides of the body the clear buff 
area is reached. The white nuchal spot exists in this specimen as a few scattered 
hairs, hardly noticeable. Ventrally the lower surface of the forearm and the 
inguinal region from tibia to tibia is suffused with ferruginous. 
The opposite extreme is shown by another female in which the black is so 
dilute, not only on the dorsal area as a whole, but in the separate hairs, that it 
appears as a distinct brownish, nearly drab of Ridgway’s Nomenclature of colors, 
grizzled with buff hairs. The latter become slightly tinged with rufous on the 
sides and venter. 
The ferruginous tint (Plate 2) is exceptionally well developed in two large 
and apparently old females and in a third smaller animal, an adult male. In 
the brighter of the two old females the buffy hairs of the back and sides of the 
head and body and on all but the mid-ventral region are replaced by ferruginous, 
even the nuchal spot being of this tint. The ventral portion of the chest and 
the lower throat where the ferruginous is brightest in other specimens, have in 
this example become so intensified that they are nearly black. The third bright 
specimen above mentioned is the most brilliant. The dark throat area is nearly 
