LUTHER BURBANK 



precision the relations of these qualities in cross- 

 bred plants of the first and second generations. 

 In so doing he reduced to a definite formula the 

 observation of the mingling of traits in the first 

 generation and their redistribution and recombi- 

 nation in the second, which Mr. Burbank has ob- 

 served to be so common a phenomenon with the 

 great number of species with which he worked. 



But Mendel went further. He formulated a 

 theory as to the causes that operate to determine 

 the relations of antagonistic characteristics when 

 brought together through the mingling of diver- 

 gent germ-plasms ; and his theory was at once so 

 simple and so satisfactory that it has now come to 

 be accepted at least as a provisional hypothesis 

 everywhere. 



According to this theory, every tangible char- 

 acteristic of any organism is determined by the 

 mingling in the embryonic germ-plasm of two 

 hereditary "factors" or "determiners," the jux- 

 taposition of which is essential to the production 

 of the character in question. If these factors 

 represent the same quality, there will, of course, 

 be no antagonism, and the quality of the resulting 

 character will not be in doubt. But if, on the 

 other hand, the two factors are antagonistic 

 one, let us say, representing a black berry and the 

 other a white berry the result may be that one 

 factor entirely dominates the other, the subordi- 

 nated character seeming to have no representation 

 whatever. 



But the factor thus submerged reproduces it- 

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