OUR FUTURE COURSE 227 



ment which we know and to gain the degree of 

 independence which is characteristic of their kind. 

 The individual responses which are commonly 

 known are of slight degree. Even if developed to a 

 maximum it is possible that they will still lack 

 adaptive value under any available conditions. 

 But stranger things than this have been accom- 

 plished and we may yet see all of these conditions 

 realized. It is certain that the previous method of 

 subjecting organisms to a stimulus for a few gen- 

 erations and then removing them to the original 

 environment is hopelessly inadequate for the in- 

 vestigation of such a complex subject as the process 

 of evolution. Succeed or fail, it is better by far to 

 follow a method which promises success than one 

 which is obviously inadequate. 



Finally I would note again that this proposal 

 does not deny in the slightest degree the efficacy 

 of other factors in evolution. The inheritance of 

 acquired characters is emphasized because it de- 

 mands investigation more than any other subject, 

 but it is broader than the term usually implies. 

 Natural selection, isolation, and other processes of 

 less importance, are also potential sources of change 

 in species, once we have a variable heritage on 

 which they may work. Our task is largely to de- 

 termine the source of variation in an originally 

 homogeneous heritage, and the response of the 

 individual to its environment is too ligtiificant 



