191 1.] Selection of Fowls for Egg Production. 663 



The second (March 1st to June 1st) is the natural laying period 

 of the domestic fowl in its normal reproductive cycle. The 

 third (June 1st to September 1st) and fourth (September 1st 

 to October 31st) are periods not sharply separated from one 

 another. The summer egg production represents in part a 

 natural continuance of the normal breeding season, and in 

 part a stimulated process. This period is terminated by the 

 moult, which is the characteristic feature of the fourth period. 



Effect of Selection on Production, — It is by no means 

 certain that there has, in recent times, been anv marked 

 amelioration in the innate qualities on which high egg pro- 

 duction depends. The egg production of a given number of 

 hens is, of course, on the average greater than it was fifty or a 

 hundred years ago, but the increased production is quite pos- 

 sibly due entirely to the improved methods of management, 

 which, had they been in vogue in earlier times, would have re- 

 sulted in just as large a production as at present. The six best 

 birds at the Maine Experiment Station have given an average 

 production of 240 eggs per bird, an amount which seems 

 to have been equalled in some cases fifty years ago {e f g., it is 

 stated in the Journal of the Royal Agricultural Society of 

 England for 185 1 (p. 169) that hens of the best laying varieties 

 will lay in a season from 160 to 270 eggs each). 



Throughout these experiments there was an increase in the 

 stringency of selection due to the fact that there was a decrease 

 in the number of birds producing over 160 eggs ; consequently 

 the variation exhibited in the selected stock became steadily 

 smaller, both absolutely and in proportion to the whole flock. 

 It was not possible to find the effect of selection on egg pro- 

 duction by tracing the production of parent and offspring, or 

 by ascertaining the degree of inheritance of the character and 

 comparing the variability in successive generations following 

 selection, as no records were kept at the Station by which it 

 could be told what birds were the parents of any particular 

 offspring. It was simply known that the eggs of high-pro- 

 ducing hens were incubated, and the conclusions have to be 

 deduced from data based on results obtained from the flock 

 as a whole. These data show that the annual egg production 

 has by no means tended to increase during eight years ; the 

 proportion of exceptionally high producers decreased, and 



