METHODS AND RESULTS OF ETHNOLOGY. 247 



alluvial plains of tropical South America, or in the 

 exposed islands of the Polynesian Archipelago, or 

 among the populations of equatorial Borneo or 

 Sumatra. No satisfactory explanation of these 

 obvious difficulties has been offered by the ad- 

 vocates of the direct influence of conditions. And 

 as for the more important modifications observed 

 in the structure of the brain, and in the form of the 

 skull, no one has ever pretended to show in what 

 way they can be effected directly by climate. 



It is here, in fact, that the strength of the Poly- 

 genists, or those who maintain that men primi- 

 tively arose, not from one, but from many stocks, 

 lies. Show us, they say to the Monogenists, a 

 single case in which the characters of a human 

 stock have been essentially modified without its 

 being demonstrable, or, at least, highly probable, 

 that there has been intermixture of blood with 

 some foreign stock. Bring forward any instance 

 in which a part of the world, formerly inhabited 

 by one stock, is now the dwelling-place of another, 

 and we will prove the change to be the result of 

 migration, or of intermixture, and not of modifica- 

 tion of character by climatic influences. Finally, 

 prove to us that the evidence in favour of the spe- 

 cific distinctness of many animals, admitted to be 

 distinct species by all zoologists, is a whit better 

 than that upon which we maintain the specific dis- 

 tinctness of men. 



If presenting unanswerable objections to your 



