140 Discussion 



In what way do non-hereditary adaptive changes gradually turn into 

 genotypic properties? To answer this question, special and more pro- 

 found investigations are required. One can well imagine that the ability 

 to synthesize a particular enzyme, trained for a long time, will finally 

 touch on some more remote enzymic systems, which pass from the 

 vegetative cell into the spores formed in it. Resulting from this, the 

 vegetative cell developed from the spore will have a greater ability to 

 synthesize a given enzyme prior to coming in contact with the external 

 inductor. This will result in hereditary fixing of this ability. 



I should like to note that the aim of my report is to draw more 

 attention to the concept — shared by many of my countrymen — of the 

 possibility of gradual transformation of acquired adaptive changes into 

 stable hereditary changes. The experimental testing of this hypothesis 

 might yield important results, which would have been scarcely possible 

 had this theory been disposed of a priori. 



It would be equally wrong to disagree, without sufficient proof, with 

 the widely acknowledged theory that mutations are the only form of 

 hereditary changes. Facts must be the highest arbiter in all scientific 

 disputes. 



