28 

 Table 6. 



Correlation in Fertility between Males' First and Second-Year Daughters. 







10 



Constants calculated from Table 6. 

 First-year daughters' mean fertility . 

 First-year daughters' standard deviation 

 Second-year daughters' mean fertility 

 Second-year daughters' standard deviation 

 Coefficient of correlation 



. 6651 db. 031064 

 .3289±. 021966 

 .7700zb. 025001 

 .2647±. 017678 

 .2151 ±.090076 



In table 6 the mean fertility of the first-year daughters was .6651 while the mean 

 for the second-year daughters was .77. There is a difference of .1049±.0399, 

 which, judged by the magnitude of its probable error, is of doubtful significance. 

 There is also no sensible difference in the standard deviation of first-and second- 

 year daughters. A sensible degree of correlation between first-and second-year 

 daughters is questionable because r = .2151 zb .090076. The probable error is almost 

 half as great as the coefficient itself. The only logical interpretation that can be 

 placed on the Hmited data in table 6 is that mean fertility in the daughters of the 

 same group of males in successive years is strikingly constant, and in the second 

 place that a positive correlation coefficient of questionable magnitude exists be- 

 tween first-and second-year daughters in fertility. More data of a similar nature 

 are required to clear up this question. 



Section 7. The Constancy of Hatchability in Males. 



The male's ability to transmit fertility is still questionable, as has been pointed 

 out in section 6. In the present section the subject of the constancy of hatchabihty 

 in the male, as measured through his daughters, will be considered. The same 

 difficulties are encountered in studying this question that have already been men- 



