"The number and variety of climbing trees in the Amazons forests are interesting, taken in connection with the fact of the very general tendency of the animals also to become climbers. All the Amazonian, and in fact all South-American monkeys, are climbers. There is no group answering to the baboons of the Old World, which live on the ground. The gallinaceous birds of the country, the representatives of the fowls and pheasants of Asia and Africa, are all adapted, by the position of the toes, to perch on trees; and it is only on trees, at a great height, that they are to be seen. Many other similar instances could be enumerated." MONKEYS. "On the Upper Amazons, I once saw a tame individual of the Midas leoninus, a species first described by Humboldt, which was still more playful and intelligent than the more common M. ursulus. This rare and beautiful monkey is only seven inches in length, exclusive of the tail. It is named leoninus on account of the long, brown mane which hangs from the neck, and which gives it very much the appearance of a diminutive lion. In the house where it was kept, it was familiar with every one: its greatest pleasure seemed to be to climb about the bodies of different persons who entered. The first time I went in, it ran across the room straightway to the chair on which I had sat down, and climbed up to my shoulder: arrived there, it turned round, and looked into my face, showing its little teeth, and chattering, as though it would say, "Well, and how do _you_ do?" M. de St. Hilaire relates of a species of this genus, that it distinguished between different objects depicted on an engraving. M. Ardouin showed it the portraits of a cat and a wasp: at these it became much terrified; whereas, at the sight of a figure of a grasshopper or beetle, it precipitated itself on the picture, as if to seize the objects there represented." THE CAIARÁRA. "The light-brown caiarára is pretty generally distributed over the forests of the level country. I saw it frequently on the banks of the Upper Amazons, where it was always a treat to watch a flock leaping amongst the trees; for it is the most wonderful performer in this line of the whole tribe. The troops consist of thirty or more individuals, which travel in single file. When the foremost of the flock reaches the outermost branch of an unusually lofty tree, he springs forth into the air without a moment's hesitation, and alights on the dome of yielding foliage belonging to the neighboring tree, maybe fifty feet beneath; all the rest following his example. They grasp, on falling, with hands and tail, right themselves in a moment, and then away they go, along branch and bough, to the next tree.