BROODINESS IN DOMESTIC FOWL. 



103 



Table I. — Kinds of Offspring expected from all Possible Kinds of Matings. 



Of the nine possible groupings between parents and offspring, six have 

 been reahzed in our experience. Those marked with an asterisk (*) have 

 not been realized. Two of the three unrealized possibilities should be 

 realized eventually, and the third, all non-broody offspring from broody 

 parents, is not expected, as is explained beyond. 



The preceding table, as well as the ratios in which the offspring occur. 

 Table II, does not agree with the assumption that broodiness is a simple 

 Mendelian dominant and non-broodiness a simple recessive in all instances 

 as Hurst (1905) supposed. If non-broodiness were a simple Mendelian 

 recessive, then the son of a non-broody hen should throw either all non- 

 broodies or half non-broodies when bred to non-broodies, but this does 

 not always happen. Moreover, the establishment of a non-broody strain 

 should have been a much simpler matter than it has proved. 



