46 



MASS. EXPERIMENT STATION BULLETIN 215. 



hatched in 1917 and 1918. Records for the flock hatched in 1919 were cut short by 

 disease outbreaks. It was found necessary to dispose of most of the stock and 

 e.xercise rigid quarantine measures. This prevented the completion of anj^ annual 

 records ckiring 1920. 



Referring again to Chart I, the mode of the flock will be observed to have ad- 

 vanced in 1920 to the 200 to 249 egg class, with a skewness indicating that the 

 mode of the flock lies considerably above the average. In other words, a bimodal 

 condition begins to present itself. 



CHART II. 



Gener.vl Classification of Birds on the Basis of Production. 



HIGH 

 3.91 fo 



MEDIUM 

 68.33^ 



HIGH 

 15.97/0 



HIGH 

 50.72^0 



LOW 

 27.76^0 



MEDIUM 

 75.28^ 



MEDIUM 



LOW 

 1.6 7/0 



BIRDS HATCHED BIRDS HATCHED BIRDS HATCHED 

 1912-1916 I9I7-I9I8 1920-1921 



The results of the season ending in 1922 indicate that the general distribution 

 of the 1921 flock conforms closely with that of 1920. The graph for 1921 also 

 shows a bimodal condition of the flock, lying in the 150 to 199 class and in the 200 

 to 249 class. 



Chart II is presented as supplementary to Chart I. Chart I shows that the most 

 common group of producers falls in the 100 to 149 egg class in the years 1912 to 



