PART ONE 

 THE DESCENT OR ORIGIN OF MAN 



CHAPTER I 



THE EVIDENCE OF THE DESCENT OF MAN PBOM 

 SOME LOWER FORM 



Nature of the evidence bearing on the origin of man — Homologous struc- 

 tures in man and the lower animals — Miscellaneous points of corre- 

 spondence — Development — Rudimentary structures, muscles, sense- 

 organs, hair, bones, reproductive organs, etc. — The bearing of these 

 three great classes of facts on the origin of man 



HE who "wishes to decide whether man is the modified 

 descendant of some pre-existing form would prob- 

 ably first inquire whether man varies, however 

 slightly, in bodily structure and in mental faculties; and 

 if so, whether the variations are transmitted to his offspring 

 in accordance with the laws which prevail with the lower 

 animals. Again, are the variations the result, as far as our 

 ignoraijcg,jftejU£Liis_u^ to judge, of the same general causes, 

 an^^e they governed^lr^sllie same general laws, as in the 

 case of other organisms; f5?SJistance, by correlation, the 

 inherited effects of use and disiisg?,®*^-^ ^^ ™^^ subject 

 to similar malconformations, the result*(S&i^^st^^ develop- 

 ment, of reduplication of parts, etc., and do^'^® display in 

 any of his anomalies reversion to some former iil~^^^®°* 

 type of structure? It might also naturally be inqulreu" 

 whether man, like so many other animals, has given rise 

 to varieties and sub-races differing but slightly from each 

 other, or to races differing so much that they must be 

 classed as doubtful species.. How are such races distrib- 

 uted over the world; and bow, when crossed, do they react 



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