28 THE RISE OF MAN. 



blood of one animal is poison when injected into the ar- 

 teries of another individual of a different genus, because 

 red blood corpuscles dissolve in strange serum. Professor 

 Friedenthal has proved, however, that kindred species 

 will not suffer greatly by an interchange of serum ; for 

 while the interchange of the serum of a cat and a rabbit 

 would be destructive to the life of either, in the case of 

 the horse and the ass, or the dog and the wolf, the results 

 are not fatal. In view of these facts it is of great interest 

 to learn from his experiments that man and chimpanzee 

 possess blood that can be similarly interchanged. 



Chimpanzees live in herds, and a company of them 

 gives the impression of a jolly frolicking party of children 

 dressed up as satyrs or fauns. They inhabit the tropic 

 parts of Africa. Besides being literally kin of blood to 

 man, the chimpanzee among all of the primates is the 

 only ape that possesses an indication of lips. Man is the 

 only animal that is in possession of two lips. All the 

 monkeys have a sharp mouth without the gentle curvature 

 which is so expressive in the human face. The chimpan- 

 zee's mouth, too, is sharply cut off, but the margins are 

 at least slightly pink in color, while those of the gorilla 

 and the orang-utan are as dark as the snouts of lower 

 beasts. 



The chimpanzee is smaller and more slender and 

 graceful than the gorilla. He is not so strong, but far more 

 intelligent. By nature he is a strict vegetarian ; but in 

 captivity he learns to take flesh and broth. As soon as 

 accustomed to it he even enjoys and prefers meat to his 

 former diet. Of one chimpanzee, who was brought 

 up in captivity, we are told that at first he refused meat, 

 but by and by he became accustomed to it and soon took 

 the same food as man. 



Chimpanzees in captivity are easily accustomed to 

 imitate human society. They sit at the table like men, use 

 spoons and even knives and forks. They also are easily 



