GENERAL 



When we have considered this preliminary ques- 

 tion, which is the most difficult yet, curiously 

 enough, perhaps the least debated of all questions 

 in evolutionary theory at the present time, we 

 must proceed to look at "organic evolution" as it 

 is commonly understood that is to say, at the 

 means by which the primal form or forms of life 

 have given rise as evolution asserts to the 

 millions of varieties of vegetable and animal life 

 with which the earth is peopled to - day. Here 

 we shall find that, while no competent critic can 

 now be found, less than half a century after the 

 publication of the Origin of Species, to dispute the 

 fact of evolution in the organic world, yet there is 

 scant agreement as to the nature and relative im- 

 portance of the factors by which this has been 

 brought about. We shall have to consider the 

 doctrine systematically propounded by Lamarck 

 in 1809 the year of Darwin's birth that the 

 modification of species has been due to the in- 

 heritance of characters acquired by individuals 

 as a result of converse with their environment. 1 

 It must be decided, if it be possible, whether this 

 inheritance of acquired characters takes place at 

 all, and, if so, what is its importance as a factor in 

 organic evolution. 



Then we must inquire into the evidence for the 

 principle which will forever be associated with the 

 illustrious name of Charles Darwin, and which he 



1 The original term used by Lamarck is ' ' milieu environ- 

 nant." 



97 



