766 MAMMALIA. 



Family i. HAPALID/E ( = Arctopithecini). Marmosets. 



The marmosets are the smallest monkeys, not much 

 larger than squirrels. They live in companies in the 

 Neotropical forests, especially in Brazil, and feed on insects 

 and fruit. 



In addition to the general Platyrrhina characters, the 

 following are noteworthy. 



Their dentition \ I is distinctive, for other Anthropoidea 

 have molars. The molars have three main tubercles 



3 



instead of the usual four. The pinna of the ear is very 

 hairy. The tail is long, bushy, and non-prehensile. The 

 pollex is long, but not opposable ; all the digits have a 

 pointed claw except the short opposable hallux. The 

 cerebral hemispheres have few convolutions. The marmo- 

 sets often bear three young ones at a birth, whereas the 

 other monkeys usually bear but one. There are two 

 genera, Hap ale and Midas. 



Family 2. CEBID^E. American Monkeys. 



The American monkeys occur throughout tropical 

 America, but are most at home in Brazil. In addition to 

 the general Platyrrhine characters, the following are note- 

 worthy. The tail is long except in Brachyurus^ and is 

 often prehensile. The digits have nails, not claws ; the 

 thumb if present is opposable. The pinnae are more or 

 less naked. The dentition is characteristic, for there are 

 six back teeth; the formula being 2133. All are uniparous. 



Examples. The howling monkeys (Mycetes), with diverticula from 

 the larynx and enormously dilated hyoid, protected by the 

 expanded mandibles ; the sakis (Pithecia) with very long 

 non-prehensile tail ; the spider monkey (A teles] with exceed- 

 ingly prehensile tail and a thumbless hand ; the capuchins 

 (Cebns], often imported into Europe. 



Family 3. CKRCOPITHECID^: ( = Cynomorph Catarrhina). 



Old World Monkeys. 



The Old World monkeys are plantigrade quadrupeds, 

 and the snout or muzzle often justifies the term Cynomorph 



