No. 581] 



INHERITANCE OF FECUNDITY 



311 



13.27 1.3.21 (1901-02, only 48 birds in small 



13.39 14.46 (1905-06, 50-bird flocks) 



17.33 18.29 (1905-06, 50-bird flocks) 



10. tv 18.50 (1901-02, only 4S birds in small flocks) 



(overfeeding of green food) in the latter part of April. 

 This adversely affected the May production. The 100- 

 bird pens were more affected than the 50-bird pens. Con- 

 sequently, in order to give every possible advantage to the 

 earlier period of the work, I have taken the 50-bird pen 

 averages for April, June and July and have graphically 

 interpolated the figure for May in the diagram. 



The data in Table I are set forth graphically in Fig. 1. 



From the table and the diagram the following points 

 are to be noted : 



1. It is apparent that the laying in the part of the lay- 

 ing year covered by the statistics was distinctly better 

 in 1913-14 than either the weighted mean of the whole 

 period of mass selection, or than in the best comparable 

 year of the earlier period. 



2. The difference is somewhat more pronounced in 

 respect of winter production (i. e., the laying prior to 

 March 1) than for any other cycle. Under the earlier 

 plan of breeding the average winter production was 36.12 

 eggs. This production corresponds reasonably closely to 

 the division point at 30 eggs between genetically high and 



7 Average from 50-bird pens of same year (1905-06). See text. 



