22 EXPERIMENTAL EVOLUTION LECT. 



name deserves a high place in the history of the rise 

 and progress of evolutionary thought, and the paper to 

 which I allude is not generally well known, even to 

 writers familiar with the subject of evolution. Of 

 Darwin's work I shall say nothing : all are familiar 

 with the principles which lie at the root of his theory ; 

 but it would be unfair not to put Herbert Spencer's 

 name on the list, close to his. 



And now we may briefly recapitulate the theories 

 which have been proposed on both sides to explain 

 the present condition of the organic world. 



On the special creation side we meet with four 

 distinct views : 



(1) Our planet, long uninhabited, has become 

 peopled with the types and forms it now contains, from 

 another planet in which these existed, and which has 

 fallen on ours. 



This hypothesis might be discussed by savages 

 or by lunatics ; to me it seems useless to show 

 its failure, of which the least is that it merely 

 puts off the problem without any attempt towards 

 solving it. 



(2) All species have been specially created from 

 the beginning of the world a very elastic term, to be 

 sure and have lived in part, or in whole, until the 

 present day, without any alteration. 



This hypothesis is untrue, as it is known that most 



