milk teeth consist of four incisors above and below, two pre-molars above and below, and four true molars above and below, making twenty teeth in all. All these animals, except the first two genera, have simple stomachs, but the liver has several fissures in it in the Baboons (as it has in the Gorilla), and but few in the Asiatic species (as in the Orangs)--facts of no small significance, for it is very probable that the Gorilla is one of the Baboon line, as the Orang is one of the genealogical tree of a Semnopithecus. The brain exhibits all the convolutions seen in the Anthropomorpha, but the very monkeyish external perpendicular one is well marked. The little brain is not uncovered by the brain proper, which is shortest in the Sacred Apes and longest in the Baboons. The description of the Cynocephali ends that of the Monkeys of the Old World--The Catarrhini--and the whole of the group may be classified as follows:-- _Class._--Mammalia. _Order._--Primates. _Family._--Catarrhini. _Sub-Family._--{1. Anthropomorpha. {2. Cynomorpha. 1. Anthropomorpha. Genus--Troglodytes. Example--The Gorilla and Chimpanzee. „ Simia. „ The Orang-utan. „ Hylobates. „ The Gibbons.[72] 2. Cynomorpha. Genus--Semnopithecus. Example--The Entellus Monkey. „ Colobos.[73] „ The Guereza. „ Cercopithecus. „ The Guenons and Mangabeys.[74] „ Macacus. „ The Magot. „ Cynocephalus. „ The Baboons.[75] CHAPTER X. THE MONKEYS OF THE NEW WORLD.[76] THE CEBIDÆ--THE HOWLERS--THE WOOLLY MONKEYS--THE SPIDER MONKEYS--THE SAJOUS. The Monkeys of the New World--How Distinguished from those of the Old--Their Division into Families--The First Family, THE CEBIDÆ, with Prehensile Tails--THE HOWLERS--Appropriateness of their Name--Where Found--General Description--THE YELLOW-TAILED HOWLER--Anatomical Peculiarities and Appearance of the Face--Other Members of the Family--THE BLACK HOWLER--Its Locality--THE WOOLLY MONKEYS--THE CAPARRO AND BARRIGUDO--First noticed by Humboldt--Peculiarities of the Skeleton--THE SPIDER MONKEYS--Seen by Humboldt in the Brazilian Forests--Remarkable Power of the Tail--Flexibility of the Limbs--Conformation of the Brain--Other Species--THE COAITA--Curious Stories of them in Captivity--THE CHAMECK--THE BLACK SPIDER MONKEY--Its Geographical Range--Its Position in Sleep--THE VARIEGATED SPIDER MONKEY--THE SAJOUS--THE CAIARÁRA--Observed by Bates on the Amazon--Other Varieties--THE BROWN SAJOU--THE CAPUCHIN SAJOU--Described by Brehm--Their Remarkable Dexterity and Cleverness--Diseases of Monkeys.