SEX-LIMITED INHERITANCE IN POULTRY 



C. B. DAVENPORT 



From the Station for Experimental Evolution, Carnegie Institution of Washington 



EIGHT FIGURES (COLORED PLATEs) 



1. SCOPE OF THE PAPER 



The problem of sex-limited inheritance has been studied by two 

 converging lines of attack. On the one hand, Doncaster and 

 Raynor ('06), Punnett, Bateson and his pupils in England, and 

 Spillman, Pearl, Morgan and others in this country have used 

 the methods of the experimental breeder; on the other hand, 

 McClung, Stevens and Wilson have used the method of cytologi- 

 cal study. The results gained constitute one of the greatest 

 advances made in biology during the present decade, if not in 

 the history of science. The details of the interpretation of the 

 facts have been modified from time to time as light has been 

 thrown upon them from new angles but we seem now to have 

 reached a formula that is satisfactory in its simplicity and is in 

 accord equally with the data of cytology and of breeding. I 

 judge it worth while to take the occasion of the presentation of 

 certain new data to review briefly the earlier experiments on sex- 

 limited inheritance in poultry and to show how the new and sim- 

 pler formula accounts for the observed facts quite as well as the 

 various interpretations of the respective authors. 



2. THE FORMULA 



The formula that I shall adopt and apply is that which Wilson 

 has proposed ('11, '11 a) as a consequence of his cytological stud- 

 ies; and which Morgan also, has reached ('10, '11, '11 a) through 

 his experimental work in breeding flies. In its apphcation to 

 poultry, in the form herein adopted, it is that sex-limited charac- 

 ters have their determiners located in the sex-chromosome. This 



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THE JOURNAL OF EXPERIMENTAL ZOOLOGY, VOL. 13, NO. 1 

 JULY, 1912 



