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Monkey. The popular name of a large group of animals, including all of the order Primates except man. The name is frequently used to comprehend the members of the following families and sub-families of the order, viz., the Simiidae (Anthropoid Apes and Gibbons), the Cercopithecidae (Old World Monkeys), the Cebidae (American Monkeys), and the Callithricidae (Marmosets). In a restricted sense, however it is only applicable to certain members of some of the above families and sub-families, and cannot be correctly applied to the anthropoid apes. The characteristics of the different species a monkeys are so varied that it is impossible to frame a general definition of them that would be applicable to all, and the limits of space preclude us from entering into a description of each species. The Cercopithecidae include the old world monkeys and baboons; they are widely distributed over Africa and Asia. The family Cebidae comprises all the American monkeys, which differ from those of the old world in having an additional molar tooth, or grinder, in each jaw, and the nostrils widely separated, while they have neither cheek pouches nor callosities, and their thumbs are never completely opposable. Some have a prehensile tail, which is as useful to them as an additional hand in their arboreal haunts. The members of this family are strictly confined to the forest regions of tropical America, from southern Mexico to northern Chili. The last family, the Callithricidae, comprises the marmosets, which are distributed from southern Mexico to southern Brazil. The habitats of all monkeys are chiefly forests, for which their structure is especialy adapted, enabling them to climb trees with ease and to leap from branch to branch with extra-ordinary agility. Here they are masters of the situation, the only foe they dread being the serpent, which alone can reach them in the arboreal retreats. Their food consists chiefly of fruits and other vegetable substances; but, in addition to these, birds and their eggs and insects are by no means unacceptable to them.