Quadrumana.
Monkeys.
The American monkeys consist of two chief families,—the Cebidae, and the Midas or Marmosets—which are again separated into thirteen genera, consisting of about eighty-six species, greatly diversified among themselves. In America neither Pithecidae or Lemurs are found: they exclusively inhabit the Old World.
The Cebidae have thirty-six teeth; the Marmosets possess but thirty-two: three of them, however, are pre-molar, as are three of those of the Cebidae, thus distinguishing them both from all the forms of the Old World.
The Marmosets are a low type of apes—their brain being smooth, and they having claws instead of nails; but from their intelligent-looking countenances, and their gentle, playful disposition, they appear to have as much sense as the larger apes.
The American monkeys differ greatly in size and form. The largest—the savage black howler—is nearly two feet
and a half in length of trunk; while the beautiful timid marmoset is so small that it may be inclosed in the two hands. Some have tails twice the length of their bodies; the caudal appendages of others appear to have been docked, or are altogether absent. The long tails of some are prehensile, and have a smooth surface, which enables them to employ it as a fifth hand; others are covered with thick bushy hair, and are employed apparently only in balancing the animal. When night comes they roll themselves into a ball, huddled together as close as may be, to keep themselves warm. Sometimes it happens that a few little monkeys have not been alert enough to get into the ball, and are left shivering outside. They keep up a pitiful howling the whole night through.
One family—the Marmosets—have, as has been remarked, claws instead of nails. Others are covered with short, coarse hair; while others, again, have coats of a long, soft silky texture.
Some sport among the branches, seeking their food in the daytime; others, again, only come forth from the hollows of trees, where they have their beds during the night season—their eyes being formed, like those of owls, incapable of meeting the glare of day.