LUTHER BURBANK 



the presentation of such a formula is to clarify all 

 the mysteries of heredity and to do away with the 

 necessity in the future as some misguided enthu- 

 siasts have assumed of laborious and patient 

 experiments akin to those through which the tri- 

 umphs of the plant developer have been achieved 

 in the past. 



In a word, the Mendelian formulas, if accepted 

 at their true valuation and for their real purpose, 

 may be regarded as placing new and valuable 

 tools in the hands of the plant experimenter, just 

 as did the formula of natural selection as put for- 

 ward by Darwin; but we must in one case as in the 

 other guard against imagining that the phrasing 

 of a formula may properly take the place of the 

 practical observation of matters of fact. 



Bearing this caution in mind, let us note the 

 changed terminology in which the Mendelian of 

 today interprets the observed facts of the develop- 

 ment of the white blackberry. His explanation 

 would run something like this: 



When the Lawton blackberry is crossed with 

 the whitish berry, all the offspring of the first filial 

 generation are black because blackness and white- 

 ness are a pair of "unit characters," both elements 

 or factors of which cannot be manifested in the 

 same individual; and blackness is the "dominant" 

 character of the two, whiteness being "recessive." 



[62] 



