LUTHER BURBANK 



dice as to the exact number of cases in which 

 shortness of stalk would be combined with the 

 bearing of yellow pods. 



PAIRING THE FACTORS 



If we assume as Mendel finally came to do- 

 that each of the different qualities about which we 

 are speaking is represented in the germ plasm by 

 a definite mechanical factor which must be paired 

 with another factor, either like or unlike itself, in 

 order to stimulate the development of the char- 

 acter it represents, then at least a provisional 

 explanation of the observed facts might be found 

 in supposing that a dominant factor when mated 

 with a recessive one hides or obscures the recessive 

 one in that particular combination; but does not 

 eliminate it. 



And when the factors are again mixed to pro- 

 duce a new generation, they are still equal in 

 number, and if we think of the factors as tangible 

 things let us say like black or white checker men 

 it will appear that if equal numbers of each are 

 mixed together and taken from a bag in pairs at 

 random or blindfold, it will come about, accord- 

 ing to the mere theory of chances, that one time 

 in four two of the white checkers will be paired. 



This accounts in a crude and mechanical but 

 on the whole a rather satisfactory way for the 

 appearance of the recessive character say short- 



[92] 



