BREEDING POULTRY FOR EGG PRODUCTION. 



157 



Certainly the first line of evidence, derived from a long-con- 

 tinued experiment, involving more than 2,000 individuals, gives 

 no support to the "statistico-ancestral" theory and indeed is in 

 flat contradiction to one of the most fundamental tenets of that 

 faith. 



36-00 OO-O] 01-02 02-03 03-04 04-OS 05-M 06-07 07-08 

 LAYING TEAR 



Fig. 8o. Diagram showing the course of average winter egg produc- 

 tion during the period covered by the mass selection experiment. 



Let us next consider the question, 



ARC SOMATICALLY KgUAL VARIATIONS IN I-KCUNDITV OF EQUAI« 

 HEREDITARY SIGNIEICANCE ? 



In the spring and summer of 1907 were reared 250 pullets, 

 all of which were the daughters of hens that had laid approxi- 

 mately 200 or more eggs in the first year of their life. This 

 group of mothers was reasonably homogeneous in respect to 

 records of egg production. All had laid about the same number 

 of eggs. Their daughters were, however, far from a homo- 

 geneous lot with, respect to egg production.* It is plain from 

 the results obtained in that experiment that the egg record of a 

 hen is a most unreliable criterion of the probable number of 

 eggs which her daughters will lay. This is demonstrated by 

 examination of individual cases. Thus consider the two mothers 

 Nos. 253 and 14. Their winter production records were nearly 

 identical (65 and 66, eggs, respectively). Their daughters' aver- 



* VvW details regarding this experiment have been published as Bulle- 

 tin 166, Me. Agr. Exp. Sta., 1909. See particularly Table I. 



