ON THE QUICK GROWING WALNUT 



be a thousand subordinate factors for form of 

 flower; a thousand others for texture of petal; a 

 thousand others for odor; yet another thousand for 

 hardiness; and so on for each and every patent 

 characteristic of flower and twig and stem and root 

 of the plant. In the aggregate, let us say, there are 

 a thousand different "unit characters," each made 

 up of a thousand minor factors, so that the total 

 number of hereditary factors stored in the germ- 

 plasm and fighting for recognition, in the case of 

 a single plant, is a round million. 



Each of these million factors has been devel- 

 oped in the long slow process of evolution, one 

 after another added, generation by generation, or 

 era by era, beginning with the time when the 

 remote primordial progenitor of the plant was a 

 single-cell organism. 



In the course of the ages, development has 

 taken place along divers lines, and it has come to 

 pass that certain combinations of hereditary fact- 

 ors have been grouped into systems that have so 

 long been working in harmony together that they 

 cannot be separated. The members of one such 

 group determine the architecture of the root; the 

 members of another group determine the archi- 

 tecture of the stem; and so on for each of the 

 patent characters. 



But there are other groups of factors that are 



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