Table 4. — Correlation in FcrlUHii Between Mother and Daughter. 



25 



Constants calculated from Table 4- 

 Dams' mean fertility . 

 Dams' standard deviation . 

 Daughters ' mean fertility ; 

 Daughters ' standard deviation 

 Coefficient of correlation 



.8765 ±.003503 

 .1479±. 002477 

 .7378 ±.006831 

 .2884 ±.004830 

 .0147±. 023679 



The standard deviation in dams in fertility is .1479, while the standard deviation 

 of their daughters is twice as great or .2884. There is a positive correlation co- 

 efficient in fertility of .0147±. 023679 between the dams and the 811 daughters 

 that were used as breeders. Since this coefficient is less than its probable error, 

 it can have no significance. This table must therefore indicate that a pullet with 

 low fertihty is as likely to give daughters high in fertiht\^ as is a breeding pullet 

 that shows high fertihty herself. These observations are essentially in agreement 

 with Pearl ('09), for he found a negative correlation of .035±.072 in infertility 

 between mother and daughter. The conclusion seems justified, therefore, that the 

 fertihty of the dam 's eggs is no indication as to the probable fertihty of her daughter's 

 eggs. In section 2, the fertility record of a puUet was shown to be a guide as to her 

 second-year fertility. Since the dam's fertility record is not a dependable index of 

 her ability to breed true for fertility, the only satisfactory test is the progeny test, 

 for fertihty seems to depend upon many as yet unrecognized factors, or else is not 

 an inherited characteristic. 



Section 5. Correlation in Hatchability between Mothers and Daughters. 

 The identical group of dams and daughters used in table 4 has again been cor- 

 related in table 5, using percentage of fertile eggs hatched. 



