ON THE NEED FOR IMPROVEMENT 



thornlessness, and in that case the future plant 

 will be thornless. 



Yet again there may be a union of a thorny 

 factor with a thornless factor; and in this case, as 

 we have seen, thorniness will prevail because, as 

 we say — although, of course, our explanation only 

 states the matter over again in another way — the 

 thorny factor is dominant and the thornless factor 

 recessive in this particular combination. 



Changing our terms to suit the case, the same 

 principles apply to our black and white black- 

 berries. 



And in each case, it will be recalled, the germ 

 cell that bears only dominant factors will breed 

 true to the dominant quality; the germ cell that 

 bears only recessive factors will breed true to the 

 recessive character; and the germ cell that bears 

 the two conflicting factors will have progeny in 

 which these factors are separated and reassembled 

 in various combinations, thus accounting for the 

 reappearance of the latent or recessive character. 

 Heredity Visualized 



All this is familiar to us and has been illustrated 

 over and over again from practical cases in the 

 course of our studies. 



And we have agreed that the really mysterious 

 part of the entire process is the fact that the 

 hereditary factors are able to combine with such 



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