LUTHER BURBANK 



These terms are of obvious convenience, being 

 somewhat parallel in their application to the Men- 

 delian terms dominance and recessiveness, yet 

 being quite distinct, as we have seen, inasmuch as 

 they apply to the relations of factors that are both 

 dominant, yet which refer to the same quality and 

 hence cannot both prevail. 



Mixed Factors in the Poppy 



Our studies of inheritance of color in the pop- 

 pies suggest that closely similar relations exist 

 among the pigments of the flowers. 



The exact relations of reds and yellows and 

 pinks and blues have not been carefully worked 

 out on a comprehensive scale, as have been the 

 pigment-relations of the coats of mice and rabbits. 

 But the evidence seems to suggest that the rela- 

 tions of red and yellow, for example, in the case 

 of the poppy, are somewhat comparable to the 

 relations of gray and black in the coat of the 

 mouse. 



That is to say, both of these are dominant to 

 white, but one of them is epistatic to the other. 



It is probable that red is superior in dominance, 

 or epistatic, to yellow, and hence that a poppy will 

 be yellow in color only when the factor for red 

 pigment is either absent or masked. 



The experiments that led to the production of 

 the blue poppy suggest the possibility that blue 



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