A COEFFICIENT OF INDIVIDUAL PREPOTENCY 

 FOR STUDENTS OF HEREDITY 



DR. J. ARTHUR HARRIS 

 Station for Kxi'kkimkxtal Evoiatiox, Cold Spiuxi; Harbor, N. Y. 

 I. The Coxcei'tiox of Prepotency 



The term prepotency conveys the general idea that cer- 

 tain individuals "are particularly apt to impress their 

 personal characters upon their offspring." Like most 

 terms of general biology it has boon applied in several 

 different connections. The much-needed threshing over 

 of the literature to separate the few measures of wheat 

 from the stacks of straw and weeds falls outside the scope 

 of this note. 



One may follow Vilmorin, Hallett, Hays and many 

 other noted breeders in the recognition of the practical 

 importance of the fact that two individuals may be 

 externally exactly alike and yet produce quite dissimilar 

 offspring, without pledging himself to any of the theories 

 of heredity in support of which it is sometimes cited. 

 The aim of the practical breeder is not to formulate or to 

 test theories of heredity but to get a strain of wheat 

 which will draw the maximum amount of flour from an acre 

 of soil or a breed of beasts that will yield the largest net 

 dividends in milk, eggs or steak. His problem is pre- 

 eminently a practical one, and one of the greatest services 

 the student of biology can render him is to provide the 



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