CLASS I. MAMMALIA: ORDER 2. QUADRUMANA. 



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ORDER 2. aUADRUMANA. 



The Quadrumana embrace four sections — the Monkey-like family, the Lemurs, the Cheiromys, 

 or Aye-rvje, and the Flying-lemurs. These differ in many important respects, yet they all agree 

 in having four hands, fitting them peculiarly for an arboral existence. In many of the species the 

 anterior limbs have but four fingers, with the thumbs confined to the hind feet. Notwithstand- 

 ing their conformation, they are all as true quadrupeds as most of the clawed mammalia, for in a 

 state of nature they appear never to walk on the hind legs, which are in fact too weak to be em- 

 ployed, as in the human subject, for the sole organs of locomotion ; and besides, the structure of 

 the foot, even in those most resembling man, is such that when on the ground it treads on the 

 side, and not on the palm. The legs also are set in such a manner as to tread outward, and thus 

 to be incapable of bearing a great weight. 



THE MONKEY-LIKE ANIMALS: SIMIAD^E. 



These, which are greatly diversified in form, are exceedingly numerous in species. They in- 

 clude the Apes, Semnojnthecs, Colobes, Guenons, or Cercopithecs, Mangabeys, Macakes, Magots, 

 Cynopithecs, and Baboons, belonging to the Eastern Continent, and, with the exception of a few 

 Barbary apes at Gibraltar, confined to Asia and Africa; and the Howlers, Lagothrix, Eriodes, 

 Ateles, Sajous, Callithrix, Saimiri, JVyctipithecs, Sakis, and Ouistitis, belonging to the Western 



, Continent. All are natives of hot countries, and are incapable of subsisting in cold and tem- 

 perate climates, except by the aid of man. 



In addition to the hands on the posterior as well as anterior members, with long and flexible 

 fingers and opposable thumbs, which constitute the primary characters of the order, the monkey 

 tribe in general is distinguished by the following peculiarities. Their incisor teeth are invariably 



i four in each jaw; and their molars, like those of man, are flat, and surmounted- by blunted tuber- 

 cles. The latter are five in number on each side of either jaw. in all the monkeys of the old con- 

 tinent, and in one very distinct tribe belonging to the new ; but most of the American species are 

 furnished with a sixth. Their canines vary considerably in size, and form a trifling projection beyond 



• the remaining teeth, to a long powerful tusk, almost equaling those of the most formidable car- 

 nivora ; and from this structure it necessarily follows that a vacant space is left between the incisors 



