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IX. 



THE DEVELOPMENT OF HUMAN RACES 

 UNDER THE LAW OF NATURAL SELEC- 

 TION. 



AMONG the most advanced students of man, there exists 

 a wide difference of opinion on some of the most vital 

 questions respecting his nature and origin. Anthro- 

 pologists are now, indeed, pretty well agreed that man 

 is not a recent introduction into the earth. All who 

 have studied the question, now admit that his anti- 

 quity is very great ; and that, though we have to some 

 extent ascertained the minimum of time during which 

 he must have existed, we have made no approximation 

 towards determining that far greater period during 

 which he may have, and probably has existed. We 

 can with tolerable certainty affirm that man must have 

 inhabited the earth a thousand centuries ago, but we 

 cannot assert that he positively did not exist, or that 

 there is any good evidence against his having existed, 

 for a period of ten thousand centuries. We know 

 positively, that he was contemporaneous with many 

 now extinct animals, and has survived changes of the 

 earth's surface fifty or a hundred times greater than 

 any that have occurred during the historical period ; 

 but we cannot place any definite limit to the number 



