340 



THE AMEBIC AN NATURALIST 



[Vol. XLV 



Large families were reared in F 2 and F 3 . The average 

 results in the three generations are given in the following 

 table. 



Same Line, D56D407 



It is evident that selection within the line here was 

 quite without effect. 



Another example of the same thing from line D31D447 

 may be given by way of further illustration. In this line 

 there was in the Fj generation a family of ten daughters. 

 Of these some were very good and some were poor lay- 

 ers. All were bred. The mean results are shown in the 

 next table. 



Same Line, D31D447 



Mean winter record of good layers and their progeny 62.5 23.75 22.00 

 Mean winter record of poor layers and their progeny 32.0 28.75 14.75 



Here again it is plain that selection within the line was 

 without effect. Many more examples of the same sort 

 might be given from the records did space permit. In 

 general there is no evidence whatever that the selection 

 of individuals of different laying records, but belonging 

 to the same fecundity genotype, produces any definite 

 or permanent effect whatever. 



Discussion and Conclusions 

 Taking into consideration all the facts which have 

 come out of this study, one is led to the following view 

 as to the composition of a flock of fowls in respect to fe- 

 cundity. In the average flock we may presume that there 

 will probably be represented a number of fecundity 



