Humboldt, in one of his geographical excursions amongst the great streams which feed the Orinoco, went far up towards their sources. Going once into an Indian cabin in those remote regions he saw a large Monkey, of a kind which he had never seen before. He named it, after the words of the natives, “The Caparro,” and from its having a peculiar furry skin which reminded him of the familiar hare-skin of home, he termed it Lagotriche, from λαγώς (a hare), and θρίξ, τριχός (hair, or fur), and thus arose the genus about to be described.
Humboldt’s new Monkey had a prehensile tail which was longer than the body, and underneath, close to the tip, there was a naked and sensitive spot of some length. It had a round and large head, a naked black face, but no beard. There were, however, smellers or long hairs around the mouth. It had long limbs and a shortish body, whose fur was long and sable-grey in colour. A good temper and a quiet disposition appeared to characterise this Monkey, and the natives said it was found in troops, and that it often stood upon its hind legs.
They have thumbs, as well shaped as those of any American Monkey, on the fore hands, as well as on the hinder extremities. They were deficient, however, in the howling apparatus, and therefore they differ from the Mycetes, and as their thumbs were noticed to be large, they differ from the next group of Monkeys, or the Spider Monkeys.
A careful examination of the skeleton shows that the outside differences are accompanied by inside ones, especially in the skeleton.
Thus, there are fourteen rib-bearing back-bones, or vertebræ, and this increase of number over the ordinary thirteen is interesting, because it makes the animal approach those lower than the Primates; then it has four loin vertebræ, and three are in the sacrum bone. There is a curious growth of the second vertebra of the neck or the axis, for its spine is trifid, and has three projections for the attachment of muscles. Finally, the long tail is very elaborate in its bony part, and seven of its bones near the root have so great a resemblance to the back-bones higher up in the body, that they have a canal like that which in the others protects the spinal marrow, which, however, does not reach further down than the lower loins. Then five of them have good strong spines, and all have the chevron or V-shaped bones underneath well grown.
This tail is quite as useful to the Lagothrix as it is to the Howlers and to the Spider Monkeys about to be considered, and they feel with, and swing and hold by it, to perfection.
The Caparro is about two feet two inches in length without the tail, and has been subsequently to its description by Humboldt called Lagothrix Humboldtii, or Humboldt’s Lagothrix.
THE BARRIGUDO.[81]
Bates says of this Monkey, that it is, with the rest of those found in the district of the Upper Amazon, arboreal and diurnal in its habits, and that it lives in troops, travelling from tree to tree, the mothers with the children on their backs; leading, in fact, a life similar to that of some Indians, and like them occasionally plundering the plantations which lie near their line of march. The Barrigudo is the “big-bellied Monkey” of the Portuguese colonists, and they are very bulky animals. They have the head clothed with grey, and they live with the Caparro mentioned above, in the same forests, and lead the same kind of life. One measured twenty-six inches in length, and the tail six, and it was the largest Monkey he saw in America, with the exception of a Black Howler, who was twenty-eight inches in length. The skin of the face of a Barrigudo is black and wrinkled, the forehead is low, and the eyebrows project; and, in short, the features resemble in a striking manner those of an old negro. It is not an active animal in the forests, and lives exclusively on fruits, but is much persecuted by the Indians on account of the excellence of its flesh as food. From information given to Mr. Bates he calculated that one troop of these Indians numbering about 200, destroyed 1,200 Monkeys a year for food. Consequently they are diminishing in numbers, and are not found on the Lower Amazon at all. Its manners in captivity are grave, and its temper is mild and confiding. Owing to these traits the Barrigudo is much sought after as a pet; but it is not hardy, and seldom survives a journey down the river.
There are five species of the Woolly Monkeys, and they are found in the valley of the Upper Amazon and along the slopes of the Andes to Venezuela and Bolivia (Wallace).