29 



tioned for fertility. Possiblj^ env-ironmental factors are of less importance in hatch- 

 abilitj^ than in fertility. Pearl ('09) believes that hatching quality is more of an 

 innate constitutional character than is fertility. If hatching quality is dependent 

 upon Mendelian factors in inheritance, the degree of correlation between hatch- 

 ability of the eggs of first-.vear daughters and the eggs of second-year daughters 

 would vary with the number of factors concerned, and vnih the degree of homo- 

 zygosity in the males for these factors. Should there be a sensible positive correla- 

 tion, it would indicate that the male as well as the female transmits hatching power 

 to the offspring. 



In table 7, the group of 51 pairs of daughters studied in section 6 is tabulated for 

 hatchability. 



Table 7. — Correlation in Hatchahilihj between Males' First and Second-Year 



Daughters. 



Constants calcnlated Jrom Table 

 First-year daughters' mean hatchability . 

 First-year daughters' standard deviation 

 Second-year daughters' mean hatchability 

 Second-year daughters' standard deviation 

 Coefficient of correlation 



.2965 ±.025445 

 .2694 ±.01 7992 

 .44S4±.031130 

 .3296 ±.0220 13 

 .2996±.0S5972 



Referring to table 7, the mean hatchal3ility of first -3'ear daughters is. 2965, while 

 the second-year daughters of the same male have a mean of .4484. The difference 

 is .1519±.0336, which is a significant difference. The second-year daughters 

 appear to be superior to the first-year daughters in hatching power. To draw any 

 conclusion, however, on such meager data would be more than hazardous. The 

 standard deviation does not differ significantly in the two groups of daughters. 



