EXPERIMENTAL EVOLUTION LECT. 



cannot have had any influence if the species do not 

 admit of some variability ; and this very variability 

 itself we consider as being in some degree the measure 

 of their operativeness and influence. 



We are thus impelled to conclude that transformism 

 admits of experimental investigation, and this is the 

 main point we wish to establish. If the present species 

 have really originated from the more or less closely 

 allied species which have lived in the past, if the 

 present has really been evolved out of the past through 

 natural agencies, without any special intervention 

 of any force, we do not see why there might not be in 

 the future forms evolved out of the present, and why 

 we could not evolve them ourselves, in part, and help 

 towards their production, through the use of the 

 methods which we believe to have been used by Nature 

 herself. If we do not succeed, we are either mistaken 

 in our general idea, or mistaken in regard to the 

 methods through which evolution is supposed to have 

 taken place ; but we can really draw no conclusion at 

 all as concerns these methods, as long as we have not 

 subjected them to experimental test. 



I do not propose to show all that can be done in 

 this line ; the matter would require more time than I 

 can devote to it, and on the other hand I am firmly 

 convinced that much is to be done of which we have 

 at present no idea at all. As Dareste rightly says : 



