xiv ECONOMICAL 169 



hopeful. But it may be that the variations which he 

 seeks to perpetuate are of the nature of fluctuations, de- 

 pendent upon the earlier life conditions of the individual, 

 and not upon the constitution of the gametes by which 

 it was formed. If such is the case, he will get no help 

 from the science of heredity, for we know of no evidence 

 which might lead us to suppose that variations of this 

 sort can ever become fixed and heritable. 



