30 



A sensible positive correlation of .2996 ±.085972 appears between first-year 

 pullet daughters and second-year pullet daughters in hatchability. Table 7 thus 

 furnishes a very small amount of evidence that hatching power is transmitted 

 through the male, and that it is a more constant character than would be possible 

 were it independent of heredity. 



Section 8. Relation between the Fertility of the Sire's Dam and His Phenottjpical 



Fertilizing Ability. 

 As there is no direct measure of a sire's phenotypical fertilizing power, it is 

 necessary to resort to the indirect, which is the average fertiUtv of his mates. The 

 degree of fertility in the sire's dam may be something of a guide to his inheritance. 

 The pertment question at this point is: Is the degree of fertility of a cockerel's 

 mother a guide to his abiUty to fertihze the eggs of liis mates? If such be the case, 

 there should be a sensible positive correlation between sire's dam's fertility and his 

 mates ' fertihty. In table 8 the dams of cockerels used throughout the eleven-year 

 period have been tabulated with the mates of these cockerels. The record of'any 

 particular dam was used against each of the mates of her son. The total number 

 of mates was 647. 



Constants calculated from Table 8. 



Sires ' dams ' mean fertility 8157zb. 004492 



Sires ' dams ' standard deviation 1694±. 003176 



Sires' mates' mean fertility 8531 ±.004587 



Sires ' mates ' standard deviation 1730±. 003244 



Coefficient of correlation — .1890± .025363 



