38 



Section 15. Relation of Sire and Son in Hatchability. 

 Table 15. — Correlation in Hatchability Between Sires and Sons. 



Constants calculated from Table 15. 



Sires' Mean Hatchability . .' 6738zb. 010274 



Sires' Standard Deviation 1986±. 007265 



Sons' Mean Hatchability 64 18 ±.009720 



Sons' Standard Deviation 1879±. 006873 



Coefficient of Correlation 0755±. 051440 



Reference to table 15 shows that the mean degree of hatchability is almost the 

 same in sires and sons. The two groups are also closely similar in standard devia- 

 tion. There is no sensible correlation between father and son in hatchability. The 

 degree of correlation here is practicallj'- the same as that observed for fertility in 

 table 14. If we are using the correct measure for a male's hatchability, there is 

 no evidence in these data to show that hatching power is transmitted from sire to 



Section 16. Mendelian Interpretation of the Inheritance of Fertility and Hatchability, 



Before entering upon a discussion of the possibihties of Mendelian inheritance of 

 factors governing fertility and hatchability, it would seem desirable to present 

 the mean records in the flock from year to year. These means are given below in 

 table 16 along with the number of birds tested each year. 



