Now between these gentle, but low-brained and dreamy lemurs, and the active, intelligent, mischievous monkeys, there is a great gap. The creatures most like them are the little Marmosets of South America, which run like squirrels among the forest trees of Brazil, feeding on bananas, spiders, and grasshoppers, and making their nests in the topmost boughs. But these marmosets are true monkeys, with expressive faces, and the peculiar wide-spread nostrils which we find in all the monkeys of the New World. For it is to South America, that land of the less advanced forms of life, that we must look for the lower kind of quadrumana, with side-opening nostrils,[153] thumbs which move in a line with the fingers of the hand, and not nearly so much across the palm as in the higher apes, and thirty-six teeth in their mouth instead of thirty-two,[154] as in man and in the Old World monkeys. None of these American monkeys ever become so man-like as the Apes of Africa and Asia, but in many ways they bring monkey-life in the trees to greater perfection, in the dense forests of Brazil and Paraguay, and even as far north as Guatemala. The lumbering heavy Gorilla of Africa, though higher in the scale, is a cumbersome fellow compared to the nimble little thumbless Spider monkeys of the Amazons, which hang by their bare tipped tails to the branches and to each other, chattering away like a troop of children as they gather the bananas and other fruits, or catch insects and young birds, or fly screaming with fear from the stealthy puma or the fierce eagle. With the trees for their kingdom, their tail for a fifth hand, and the warm sun to cheer and invigorate them, these spider-monkeys and their quieter friends the Capucine monkeys (often seen on London organs), and the Woolly monkeys (Fig. 65), lead a pleasant life enough, till misfortune or old age overtakes them. Their friends the Howler monkeys, which also have grasping tails, seek the deep recesses of the forest and creep quietly from tree to tree until night comes, when hundreds of them at once will make the woods re-echo with their deep howling cry, which they produce by a special voice-organ in their throat; and with them come out the little Owl monkeys, which sleep by day in the hollows of the trees. These, with the various kinds of Saki monkeys, which cannot cling by their tails, but have fairly good brains and quick intelligence, make up the monkey population of America. [Illustration: Fig. 65. A Woolly Monkey and child (Lagothryx Humboldtii), showing grasping tail. (Proc. Zool. Soc.)]