168 DOCTRINE OF EVOLUTION 



apes, the human wisdom teeth are degenerate ; in the 

 gorilla they are cut at the same time as the other molars ; 

 and in the lower human races they come through the 

 gums in early youth, while in the more advanced 

 Caucasic races they are cut only in later life or not at 

 all. The reduced vermiform appendix of man, a source 

 of much ill health, is another structure that is a counter- 

 part of a relatively larger and useful part of the digestive 

 tract in the lower primates and other animals. Further- 

 more, the human tail is a reality, not a fiction. Now 

 and then an individual is born with a tail that may 

 reach a length in later life of eight or ten inches ; such 

 structures are, of course, abnormal. But in every nor- 

 mal human being there is a series of little bones at the 

 lower end of the vertebral column, constituting the 

 coccyx, and this is just where the abbreviated tail of 

 the ape and the still longer prehensile tail of the mon- 

 key arises from the body. Unless the coccyx is a tail, 

 what can it be? And if it does not represent a re- 

 duced counterpart of the tails of other mammals, what 

 does it represent ? 



Many of the vestigial structures of man appear more 

 clearly in infancy and in embryonic development. 

 The human embryo possesses a complete coat of hair, 

 called the lanugo, which usually disappears before birth. 

 This hah* cannot be regarded as any less significant 

 than the coat of hair which the infant whale possesses ; 

 it means a completely haired ancestor. The elements 

 of this coat are arranged precisely as they are in the 

 apes; upon the arm, for example, they point from 

 shoulder to elbow and from wrist to elbow. Unless 

 the anterior limb of the hairy human ancestor was held 



