CLASS I. MAMMALIA: ORDETl 2. QUADRUMANA. 
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ORDER 2. aUADRUMAWA. 
Tlie Quadnimana embrace four sections — the MonJcey-like family, the Lemtirs, the Cheirmnys, 
or Aye-aye^ and the Flying-lemurs. These diflfer 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 era- 
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 JE. 
These, which are greatly diversified in form, are exceedingly numerous in species. They in- 
clude the Apes^ Semno])ithecs^ Colobes, Gueno7is, or Cercopithecs, Manc/abeys, 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 Hotolers, Lagothrix, JSriodes, 
Ateles, Sajous,Ca.llithrix, Saimiri, Nycti'pitliecs, Sakis, and Ouisiitis, belonging to the Western 
Continent. All are natives of hot countries, and are incaj)able of subsisting in cold and tem- 
perate climates, except by the aid of man. 
In addition to the hands on the posterior as w^ell 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 
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 
