No. 581] 



IXIIERITAXCE OF FECUNDITY 



313 



flock of 192 birds from November 1 to November 1 a total 

 of 166.18 eggs. This value, as a matter of fact, is very 

 close to the average production per bird of those (53) 

 out of the 192 which were kept over for experimental pur- 

 poses a second year. The corresponding total for the 

 weighted mean animal production over the whole period 



4. 'Faking the artificial year given in next to the last 

 column of the table it is seen that in 1913-14, with 125-bird 

 flocks, the November, December and March averages were 

 higher than the highest made in the corresponding months 

 during the mass-selection period, regardless of size of 

 flock or other conditions. The April, May and July aver- 

 ages in 1913-14 were substantially equal to the highest 

 made in the corresponding months under mass-selection. 

 The highest January. February and June averages in the 

 mass-selection period were from 1 to 2 eggs higher than 

 the corresponding months in 1913 14. Taking the totals 

 of the whole 9-month period compared, we have for the 

 artificial year, made up of the highest mean monthly pro- 

 duction under mass selection for each month regardless 

 of the year or the flock size, a total of 133.73 eggs per 

 bird, while that for the single year 1913-14 is 135.82. 



Another comparison, which brings out some additional 

 facts, is set forth in Table II. Any bird laying 18 or more 

 eggs per month in the months November, December, Jan- 

 uary and February may certainly he regarded as a high 

 winter producer. The proportion of such high pro- 

 ducers in the whole flock gives valuable additional infor- 

 mation to that furnished by the means, since the monthly 

 egg production variation curves are distinctly skew. The 



