CHAPTER XI 



Physical Qualities of the Chimpanzee — His Social Habits — Mental 

 Characteristics 



PHYSICALLY considered, the chimpanzee very closely 

 resembles man, but there are certain points in which 

 he differs both from man and from other apes. We may 

 notice a few of these points. The model of the ear of the 

 chimpanzee closely resembles that of man, but the organ is 

 larger in size and thinner in proportion. It is very sensi- 

 tive to sound, but dull to touch. The surface is not well 

 provided with nerves. He cannot erect his ear, as most 

 animals do, by the use of the muscles at the base ; but, 

 like the human ear, the muscles are useless, and in this 

 respect the ear is fixed and helpless. 



The hand of the chimpanzee is long and narrow. The 

 finger bones are larger, in proportion to their size, than 

 those of the human hand. One thing peculiar to the hand 

 of the chimpanzee is that the tendons inside of the hand 

 (those called the flexors), which are designed to close the 

 fingers, are shorter than the line of the bones. On this 

 account the fingers of the ape are always held in a curve. 

 He cannot straighten them. This is probably due to the 

 habit of climbing, in which he indulges to such a great 

 extent. He also indulges in the practice of hanging sus- 

 pended by the hands. In making his way through the 



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