CLASS I. MAMMALIA: 
ORDEK 2. 
QUADRUMANA. 
99 
3. MONKEYS OF THE NEW WORED : 
PEATYKKHINiE. 
These, which embrace a great variety of species, are divided by 
naturalists into two tribes or families — Cebidce, from the Greek, 
kebus, a monkey; and UapaUdce, from the Greek, hapalos, tender — 
each embracing nmnerous genera. By most naturalists the Pla- 
tyrrhince are not considered as true monkeys, and hence the term 
Siynia is restricted by them to the apes and monkeys of the Old 
World; while Simiodce includes those of both hemispheres. 
The monkeys of the family Cebidce have thirty-six teeth in all, the molars being six in number 
on each side of each jaw, instead of five as in the apes and monkeys of the other continent. The 
face is usually naked, but frequently surrounded by tufts or bushes of long hair, Avhich give these 
creatures a singularly whiskered appearance. They have neither cheek-pouches nor posterior 
callosities, which are usually possessed by the Old- World monkeys. Their fingers are all fur- 
nished with flat nails, but the thumbs are sometimes deficient on the anterior members : their 
tails are always long, and generally prehensile. They are light and elegant in their forms, and 
exhibit wonderful agility in their movements, although they are inferior in strength to the mon- 
keys of the eastern hemisphere. Their food is various ; that of some species consisting almost 
entirely of insects, while others feed principally on fruits. The majority, however, appear to de- 
vour indiscriminately almost any thing that comes in their way — such as fruits, seeds, insect*, 
eggs, and small birds. They are generally of diminutive size, and appear to be of a milder and 
more tractable disposition than their Old-World brethren. 
In climbing about in the trees, the prehensile tails are of the greatest service to them; they 
serve, in fact, as a kind of third hand. This is especially the case with the Spider Monkeys, in which 
the tail appears to possess the greatest amount of prehensile power. They often suspend the 
whole weight of the body upon the tail alone, and its delicacy is so great that the animals can 
pick up small objects with it. The Spider Monkeys are destitute of thumbs on the ;anterior limbs. 
The Howling Monkeys are remarkable members of this family. In these the hyoid bone and 
thyroid cartilage are of immense size, and the former constitutes a bony case, which receives a 
large pouch communicating with the larynx. It is by the reverberations caused by this appa- 
ratus that the Howling Monkeys produce those tremendous sounds from which they have received 
their name, and which, when heard in the heart of the forest, are said to have a most appalling 
efi"ect. 
In the Hapalidce, or Marmosets, there is the same number of teeth as in the Old-World apes ; 
but the tubercles of the molars are acute, indicating the insectivorous habits of the animals. Not- 
withstanding this peculiarity in the dentition, however, they resemble the ordinary American mon- 
keys in their general structure. They are all small, about the size of a large squirrel ; their heads 
are rounded, and their ears, usually furnished with a tuft of hair, stand out on each side. The 
hind-feet are provided Avith an opposable thumb, which bears a flat nail ; but all the other fingers 
of both pairs of extremities are armed with sharp claws, and the thumb of the anterior members 
