PART I. 



THE DESCENT OR ORIGIN OF MAN. 



CHAPTER I. 



THE EVIDENCE OP THE DESCENT OP MAN FROM 

 SOME LOWER FORM. 



Nature o£ the evidence bearing on the origin of man— Homologous 

 structures in man and the lower animals— Miscellaneous points of 

 correspondence— Development— Rudimentary structures, muscles, 

 sense-organs, hair, bones, reproductive organs, &c. — The bearing of 

 these three great classes of facts on the origin of man. 



He who wishes to decide whether man is the modified descend- 

 ant of some pre-existing form, would probably first enquire 

 whether man varies, however slightly, in bodily structure and in 

 mental faculties; and if so, whether the variations are trans- 

 mitted to his offspring in accordance with the laws which prevail 

 with the lower animals. Again, are the variations the result, as 

 far as our ignorance permits us to judge, of the same general 

 causes, and are they governed by the same general laws, as in the 

 case of other organisms; for instance, by correlation, the inherited 

 effects of use and disuse, &c.? Is man subject to similar mal- 

 conformations, the result of arrested development, of reduplica- 

 tion of parts, &c., and does he display in any of his anomalies 

 reversion to some former and ancient type of structure ? It might 

 also naturally be enquired whether man, like so many other ani- 

 mals, 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 dis- 

 tributed over the world; and how, when crossed, do they react 

 on each other in the first and succeeding generations? And so 

 with many other points. 



The enquirer would next come to the important point whether 

 man tends to increase at so rapid a rate, as to lead to occasional 

 a 



