INHERITANCE OF WINTER EGG PRODUCTION 



117 



high females, class II males throw half high and half mediocre, 

 while class V throw only mediocre. Neither Pearl nor myself 

 have many satisfactory data on such males. Pearl notes but 

 one class I male, and this one mated to 10 females had an average 

 progeny per mother of 1.8 daughters. There were four class II 

 males. They have a total progeny of 35 daughters and an 

 average of 2.7 daughters per mother. These families are wholly 

 unsatisfactory. No class V male appeared. 



Several Rhode Island Red males have appeared that throw 

 all or nearly all high producers, but not all kinds of females were 

 mated to them. Two class II males are recorded. The number 

 of progeny of one is small while one of the mates of the other 

 gave a ratio of 11 high: 4 mediocre: zero against an expected 

 ratio of 7| high: 7^ mediocre: zero. No class V male appeared. 



It is somewhat difficult to ascertain even roughly the propor- 

 tion in which the males of the various classes should be encoun- 

 tered, though it is clear that class V males are to be expected 

 only rarely. If we assume that the proportions given in a 

 preceding paragraph are approximately correct, then classes 

 I and II should appear at least as frequently as VII and at 

 least half as frequently as ///. They do not do so, however 

 (table 9). 



It appears probable that the validity or non-validity of Pearl's 

 theory could be demonstrated beyond doubt by first obtaining 

 males supposed to belong to classes /, II, and V and then breed- 



TABLE 9 

 Observed numbers of males in each class as determined by Pearl's theory 



* This includes males inadequately tested because mated to high producing 

 females only. 



