(32) 



Or, to look at the question from another side, just as 

 species were found to consist of a number of pure lines, 

 diverse frorr each other in minor details of genetic con- 

 stitution, so we may think of pure lines as made up of a 

 number of individuals, differing from each other in even 

 smaller details which are, nevertheless, hereditary. 



According to this idea, we can assume that each indi- 

 vidual inherits, in general outlines, the genetic consti- 

 tution of its species; in smaller details, that of its 

 pure line; in still more minute details, that of its in- 

 dividual parent; and yet may differ from this parent in 

 some hereditary points. If these individual hereditary 

 differences are fairly large, they may be referred to as 

 mutations. If they are very minute, tjiey can be termed 

 genetic fluctuations, micro-mutations, or any other term 

 which is found to meet the needs of those who work in 

 this field. 



So far as our present knowledge goes, either of 

 these two views may be championed with equal success. 

 The final decision between them must be left to the 

 experimental results of the future. 



