Probably one of the most extraordinary-looking creatures in the world is _Ateles cucullatus_ (Gray). This very spidery-looking Monkey has a very curious head of hair, which looks as if it sadly required cutting, for it comes over the forehead, and forms a regular hood, which expands over the eyebrows. Everywhere the fur is long and flaccid, and of a blackish silvery-grey colour. The face is reddish, the cheeks and lower jaw being nearly bare of hair; the skin, however, is of a black shade. The skin around the orbits and upon the nose is bare, and of a brownish flesh-colour. The body is about fourteen inches, and the tail twenty-seven inches in length. The tail is stout near the body, and becomes very slim towards the end, the greater part of it, especially the under surface, being extremely hairy. The length of the hind feet, the long scraggy limbs, the spare, long body, and its great agility, give the Monkey a most extraordinary appearance. Probably it comes from the northern coast of Columbia. There are many species of Ateles, and they range on the Pacific side of Guatemala, on the west side of the Andes, and in the forests watered by the great rivers. THE SAJOUS, OR CAPUCHINS.[88] If attention has been paid to these descriptions of the groups of American Monkeys already dealt with, it will have been evident that they can readily be distinguished one from another. Thus, the Lagothrix has a round head without a beard, a prehensile tail, with the hair off it underneath, not far from the tip, and its thumbs are large; the Spider Monkeys, or Ateles, have small heads, the same kind of tail, and their thumbs are either defective or wanting altogether; and the Mycetes, or Howlers, have high heads and beards, thumbs, the same kind of tail, and the howling apparatus in perfection. Now, the next (and last) genus of prehensile-tailed Monkeys differs from all these in not having the naked spot on the under side of the tail, in having a thicker tail, and a gentle whistling voice. These are the little “masters of the woods,” according to Azara, and should be called “Cai” (the “C” is soft), which has been altered to Sajou by the extraordinary talent which the French have of confounding spelling and sounds in other languages. Buffon divides the Monkeys noticed above into the _Sapajous_ and the _Sagoins_, the larger kinds belonging to the first, and those about to be noticed to the last. He modified, he says, the words _Cayonason_ and _Cagoni_, their _C_ being pronounced as _S_. But Azara says that the real words are Caigonazon and Cai, they being pronounced as written, and the first means Great Cai, and the last Cai, or Cay, simply Monkey. Sajous is a derivation from Cagoni, and animals properly included by it constitute the genus _Cebus_, but to add to the confusion, Mr. Wallace calls them “Sapajous.” [Illustration: BLACK AND VARIEGATED SPIDER MONKEYS. (From the _Proceedings of the Zoological Society_.)]