Among the most curious of the monkey tribe are the ateles, or spider-monkeys,--called also Cebidae, and, by the natives sapajous, one of the species of the coaita, or quata. As they are seen gambolling among the trees, with their long limbs, and still longer tails, ever actively employed, their resemblance to huge spiders is remarkable. Not that the creature is always in a state of activity, for it will often sit swinging slowly backwards and forwards, or place itself in the oddest of attitudes without moving a limb, as if resting after its exertions, or, in a contemplative mood, watching the proceedings in the world below. Sometimes a whole colony may thus be seen, when the native huntsman, approaching with his deadly blow-pipe, can without difficulty pick them off one by one, and secure his prey. But let them be alarmed, and away they go through the forest, swinging themselves from bough to bough, at a rate which no other creature, without wings, can exceed. In the spider-monkeys, the tail, as a prehensile organ, reaches its highest degree of perfection, and they may therefore be considered as the extreme development of the American type of apes. Their tails are endowed with the most wonderful degree of flexibility. They are always in motion--except when the animal is perfectly at rest--coiling and uncoiling themselves, like the trunks of elephants, seeking to grasp, apparently, whatever comes within their reach. The coaita can apply its tail to all sorts of uses. So delicate is its touch, that one would almost think it possessed the power of sight. Should it discover a nest of eggs or any creature in a crevice too small for its paw to enter, it inserts the end of its tail and hooks out the tit-bit. The animal is of considerable size, and is covered with coarse black hair--with the exception of the face, parts of which are of a tawny flesh-coloured hue. There are various species, each of which has its peculiar district; and they vary slightly in appearance. In the neighbourhood of Obydos, the Ateles paniscus has its abode; while in the Upper Amazon the white-whiskered coaita (Ateles marginatus) takes its place. It is remarkable that animals which apparently have the means of moving without difficulty at a rapid rate in any direction should thus be confined to particular localities. THE CHEMECK.