50 MAN AND APES. 



furnished with a prehensile tail, which serves 



as an important aid in climbing, and is a 



structure quite absent throughout the Simiadce, 



The apes of the New World also differ in 



having an extra grinding tooth on each side 



of each jaw, and in the fact that their thumbs 



are never opposable like those of the Simiadce 



and of Man, but bend almost in the same 



plane with the fingers. Also the septum 



between the nostrils is broad instead of narrow. 



The Cebidcenxe subdivisible into iive smaller 



groups or sub-families : — 1. The Cebince ; 



2. Mycetince ; 3. Pitheciince ; 4. Nyctipithecince ; 



and 5. Hapalirwe. 



The sub-family Cebince contain the genera 

 Ateles and Cebus. 



The Spider Monkeys Ateles are, as their 

 name implies, long-limbed and slender, but 

 their hands are as thumbless as are those of 

 the African apes before noticed. 



Their long tails are strongly prehensile and 

 naked beneath towards the tip, for more secure 

 prehension. So powerful is their grasp that 



