470 



POULTRY CULTURE 



bred together and also with the parent forms the behavior of this 

 latent character and of the corresponding dominant character seemed 

 to follow a definite law, there being approximately fixed ratios of 

 frequency of occurrence of such contrasted characters in each pos- 

 sible combination of parent forms ; (3) that certain individuals in 

 which a latent or recessive character reappeared in this generation 

 were pure as to that character, while a like number presenting the 

 dominant character were pure as to that character, and a number 

 equal to these two classes combined had the dominant character 

 but would not certainly produce offspring having it ; (4) that in 

 breeding from this last class there would be regularly produced the 

 same proportions of pure dominants, pure recessives, and individ- 

 uals in which the visible character did not correspond with the 

 germ character. 



It is plain that, if this was a correct interpretation of his results, 

 Mendel had discovered and formulated a law of great importance 

 to practical breeders. But Mendel's own interpretation of his re- 

 sults was faulty in these respects : (i) attributes which were prop- 

 erly grades of characters he regarded as "" opposite " and " mutu- 

 ally exclusive " characters, and (2) he did not discriminate carefully 

 in the examination and description of his results. The modem dis- 

 ciples of Mendel have generally persisted in these errors, and are 

 only now beginning to avoid them and to present their results so that 

 practical breeders will give them serious attention. Furthermore, 

 in nearly all Mendelian discussion it has been assumed that Men- 

 del's law related especially to cross-breeding, and that its principal 

 practical application would be to the making of new breeds and 

 varieties, while poultry breeders as a class are most interested in 

 perfecting established races, and discourage the multiplication of 

 varieties. To be of direct use to the mass of poultry breeders the 

 facts of Mendelism must be demonstrated with pure-bred poultry 

 and the laws stated for direct application in the breeding of pure 

 races. In all the confusion on this subject it seems clear that the 

 behavior of characters in transmission is less eccentric than has 

 been supposed, and that it may be possible to devise systems of 

 breeding and of record keeping which will enable breeders to 

 identify those individuals which breed true as to desired char- 

 acters, and to eliminate more certainly and rapidly from their flocks 



