POULTRY NOTES — 1909. 



103 



The constants of variation calculated from these data are 

 given in Table 11. 



Table ii. 



Coiistaufs of J\iriatioii in Egg Production in Hybrid and Pure 



Bred Pullets. 



Mating. 



Mean. 



Standard 

 deviation. 



Coefficient of 

 variation. 



Barred Rock cf x Cornish 5 



Cornish cf x Barred Rock 9 



Barred Rock ^ x Barred Rock 5 



Cornish cf x Cornish ? 1909 



Cornish j- x Cornish ? 1908 



30. .5.5 ± 1.90 

 19.07 ± 1.2.3 

 32.09 ± 0.70 

 9.08 ± 1.33 

 15.66 ± 1.59 



18.72 ±1.35 

 15.83 ± 0.87 

 17.74 ±0.49 

 8.62 ±0.94 

 11.77 + 1.12 



61.29 ± 5.83 

 83.05 ± 7.01 

 55.28 ± 1.93 

 94.91 ± 7.38 

 75.18 ± 10.47 



From these tables the following points are to be noted : 



1. There is a very marked difference between the pullets of 

 the two pure breeds in winter egg production in the present 

 year. This difference is greater in 1909-10 than in 1908-09 

 (Cf. table 2, page 85). The chief reason is that in 1908 there 

 were a few exceptionally high winter layers, for that breed, 

 among the Cornish. The 1909-10 winter production average 

 for the Cornish probably represents nearer the true breed aver- 

 age than the 1908-09. Furthermore the Barred Rocks at the 

 Station were in 1907, when the present writers began breeding 

 them, in very poor condition as regards egg production, owing 

 to a variety of circumstances not necessary to discuss here. In 

 1908-09, while there was an improvement of about 7 eggs in 

 the average winter production over 1907, they were still con- 

 siderably below the normal average winter production of the 

 strain. This normal average winter (November i-March i) 

 producticMi, determined from 8 consecutive years of trapnesting. 

 is for the Station Barred Rock stock 36 eggs. In 1909-10 the 

 winter production of the Barred Rocks is a]:)proaching tliis 

 average reasonably closely. 



2. Since all birds were kc])t under the same environmental 

 conditions as to housing, feed, management, etc., and all these 

 conditions were favorable to good egg production, the differ- 

 ences in the winter j^roduction in t 909- 10 between pure Barred 

 Rocks and pure Cornish are to be considered as innate, breed 



