UAKARI MONKEYS. 
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face was pale and mottled, the glowing scarlet hue not supervening in these animals 
before mature age; it had also a few long black hairs on the eyebrows and lips. 
The frisky little fellow had been reared in the house amongst the children, and 
allowed to run about freely, and take its meals with the rest of the household. 
“ The uakari is one of the many species of animals which are classified by the 
Brazilians as mortal , or of delicate constitution, in contradistinction to those which 
are duro, or hardy. A large proportion of the specimens sent from Ega die before 
arriving at Para, and scarcely one in a dozen succeeds in reaching Rio Janeiro 
alive. The difficulty it has of accommodating itself to changed conditions probably 
has some connection with the very limited range, or confined sphere of life, of the 
species in its natural state, its native home being an area of swampy woods, not 
more than about sixty square miles in extent, although no permanent barrier exists 
to check its dispersal, except towards the south (where the Amazon flows), over a 
much wider space.” 
Mr. Bates then goes on to relate how he had a captive uakari on board his 
vessel, at the mouth of the Rio Negro, which escaped into the forest. On the day 
after its escape it, however, reappeared, and took up its accustomed position on the 
vessel, having evidently discovered that the forests of the Rio Negro were by no 
means so suited to its existence as those of the delta-lands of its native Japura 
River. Uakaris are never known to descend of their own accord to the ground, 
the forests inhabited by them being inundated during the greater part of the year. 
Hence the shortness of their tails is no indication of their habits being more 
terrestrial than those of the long-tailed sakis. 
Other Species. 
Red-Faced On the western side of the Putumayo River the bald uakari is 
uakari. replaced by a closely allied species, known as the red-faced uakari 
( U. rubicunda), which appears to have an equally confined distributional area, 
although the exact western limits of its range are unknown. This uakari differs 
from the preceding by the hair of the body and the limbs being of an almost 
uniform rich deep chestnut hue, only becoming rather paler on the neck. This is 
in marked contrast to the pale sandy white, tending slightly to rufous, on the 
under-parts and the inner surfaces of the limbs, characteristic of the bald-headed 
uakari. Both species agree, however, in their brilliant scarlet faces, and in having 
hair of a rich chestnut tint beneath the throat; and there can be no doubt but 
that they are extremely closely related, and have acquired their slight differences 
of coloration by being now completely separated from one another, although 
descended at no very distinct epoch from a common ancestor. 
Black-Headed The most northerly representative of these monkeys is the 
Uakari. black - headed uakari ( U. melanocephala), which is found in the 
forests to the north of the Rio Negro, especially on the Cassiquiare and the Rio 
Branco. It thus enters the basins of both the Amazon and the Orinoco, so that it 
has a considerably larger distributional area than either of the other species, from 
both of which it is widely different in coloration. 
The general colour is blackish, but the back and sides of the body are 
