A'TELES, a genus of Sapajoes, or American Monkeys, called also Spider Monkeys, formed by M. Ocoffroy St. Hilaire, and presenting numerous and remarkable modifications of organic 'structure, which readily distinguish them from all other groups of Quadrumana. The most prominent characters of the gonna cousdat in their long, atteme Meal, and powerfully prehensile tails; fore hands either entirely deprived of thumbs, or having only a very small rudiment of that organ ; and their dental system, which, like that of all the American Quadnimanes, consists of two molar teeth in each jaw (one on each side) more than are fennel either in man or in the kindred genera of the Old World. The first and last of those modifications are common to the A eke and other American genera ; the second is shared with them only by the Ca/obi, a small Ateliers!' genus, consisting only of two species, neither of which has been observed by any zoologist since the days of Pennant, I with whose other characters we are very imperfectly acquainted. The A bits are further distinguished by their email round halide, corpu lent bodied', and remarkably long slender Ernie', which eharneterist ice giving these umbrella much of the general appearance of a spider, have procured for.them the appellation of Spider-Monkeys, by which they are commonly known. Like the other Quadranzana of the New World, they arc destitute of check-pouches and callosities—characters which approximate them in some measure to the real Apes. The skull of the Aides is rounder and the brain larger than in the common • the forehead also is more elevated, and the muzzle less prominent. The eyes are widely separated from one another by the base of the nose ; the nostrils open laterally, and are separated by a thick carti laginous partition ; the ear only differs from that of man in having no inferior lobe ; the mouth is small, the lips thin and extensible, and the hair generally long, coarse, and of a glossy appearance.
But they are chiefly distinguished by the organs of locomotion. The anterior extremities, in particular, are by their length and the slender ness of their form out of all proportion with the other parte ; they are in general, as above observed, destitute of thumbs ; or if some species are provided with this organ, it is only in a rudimentary form, and consists merely of a flat nail, or at most of a single joint. On the posterior extremities, on the contrary, the thumb is largely developed; placed far back towards the heel, and is completely opposeable to the fingers. But these animals possess, in their long than muscular tail,
an organ of prehension much more powerful than the other extre mities; it executes in fact all the functions of a fiftb limb, though probably, on account of its distance from the seat of sensation, it is not endowed with a very delicate sense of touch. For six or seven inches from the point it is naked and callous on the under surface ; and it is by this portion that the animal bangs suspended from the branches, or swings itself from tree to tree with an ease and velocity almost incredible.
Their entire organisation is adapted exclusively to an arboreal life; on the earth nothing can be more awkward and embarrassed than their motions. They trail themselves along with a slow and vacillating gait, sometimes using their long fore-arms as crutches, and resting upon their half-closed fists whilst they project the body and hind legs forward ; at other times walking in a crouching position on the hind legs only, balanced by the long arms and tail, which are elevated in front and rear respectively, and always ready to take advantage of any object by which to avail themselves of their natural powers of progression. But in proportion to their embarrassment on a plain surface is their dexterity and agility among the trees of their native forests. Here they live in numerous troops, mutually support one another in danger, beat and expel the leas favourably organised Sakis from the vicinity of their cantonments, and exercise a perfect tyranny over all the other arboreal mammals of their neighbourhood. Though leaves and wild fruits compose the principal part of their food, yet they do not reject flesh, but hunt after inaects and theseggs and young of birds, and are even said to adopt the stratagem of fishing for crabs with their long tails. They are exceedingly intelligent, easily domesticated, and soon become strongly attached to those who treat them kindly : they exhibit none of the petulance and insatiable curiosity of the common monkeys ; their character, on the contrary, is grave, and approaches even to melancholy: but if their passions are less violent, and more difficult to excite, their affections are infinitely stronger; and if they are without the amusing tricks of the monkeys, so likewise are they without their fickleness and mischief.