374 



BRANCH CHORDATA 



The Saki monkeys {Pithe'cia) of tropical South America east of the Andes 

 have long, bushy, non-prehensile tails, and, sometimes, a long, black chin 

 beard. 



The squirrel monkeys {Sai'miri) are little creatures with a long head, the 

 occiput projecting. The proportions of the cranium, as compared with the 

 face, are greater than in other monkeys or in man. They are gregarious and 

 arboreal, feeding upon insects, small birds, and eggs. 



The howlers are the most hideous looking of the American monkeys and 

 have the least intelligence. The brain is less convoluted than that of the 

 At'eles. Their howl, made to intimidate enemies, can be heard two miles. 



Fig. 298. — Spider monkey. (American Museum of Natural History.) 



The natives hate the howlers and kill them for food, selling the hide to white 

 traders. The hair is twisted into cordage. 



The spider monkey (Ateles) (Fig. 29S) is the most typically arboreal 

 of American monkeys. With its prehensile tail held erect over its head, it 

 "feels" for a place to grasp, which it does by wrapping the end of its long 

 slender tail tightly around the branch. It then swings itself far across 

 toward another limb, which it grasps with its thumbless hands by hooking 

 them around the limb and thus suspending its body. "They have a very 

 uncanny look and can come as near tying themselves into a knot as any liv- 

 ing mammal can." They are weak and cowardly. The Mexican spider 



