8 LUTHER BURBANK 



flowers of widely different orders, that Professor 

 Biffen was able to analyze the diverse qualities 

 of the various wheats with which he experi- 

 mented and to discover that different groups of 

 unit characters operated differently in heredity. 

 Some of the pairs showed dominance and reces- 

 siveness; others showed an irregular or partial 

 dominance; while other pairs showed the 

 blending of characters, so that the offspring 

 was intermediate between the parents, there 

 being no apparent tendency to dominance or 

 recessiveness. 



Yet all of these characters, whether manifest- 

 ing the phenomena of dominance in the hybrid 

 of the first generation or not, showed the same 

 tendency to segregation in the succeeding gener- 

 ation, and to segregation along the familiar 

 Mendelian lines; that is to say, one offspring in 

 four would reveal the first character only, the 

 second and third offspring were mixed as to the 

 pair of characters, and the fourth would show 

 only the second character. 



It was necessary only to plant the individual 

 grains of wheat in plots by themselves, and to 

 note the qualities of the grains of each (that is 

 to say, the qualities of the offspring of the first 

 filial generation) to make sure as to the position 

 of each individual in the Mendelian scale 



