BULLETIN No. 166. 



DATA ON THE INHERITANCE OF FECUNDITY 

 OBTAINED FROM THE RECORDS OF EGG PRO- 

 DUCTION OF THE DAUGHTERS OF "200-EGG" 

 HENS.* 



Raymond Pearl and Frank IVI. Surface. 



In 1907 the experiment of the Station in breeding Barred 

 Plymouth Rocks for high egg production which had been going 

 on since 1898 came formally to an end. There was planned for 

 1908 a new experiment designed to test from another standpoint 

 the conclusions which had been tentatively reached from the 

 earlier experiment. It had been noted, though never particu- 

 larly discussed in the bulletins describing the breeding work of 

 the Station, that the daughters of the so-called "registered hens 

 (namely hens that had produced 200 or more eggs each in the 

 pullet year) did not usually make high egg records. The "200- 

 egg' birds which made up the "registered" flock came in most 

 instances from "unregistered" mothers. It seemed desirable 

 to determine exactly what would be the egg production of the 

 daughters of "200-egg" hens, when these daughters were 

 accorded the same treatment as is given to other pullets. 

 Accordingly the Director of the Station and the late Professor 

 G. M. Gowell outlined an experiment to test this point. The 

 plan of the experiment was as follows : To hatch in the spring 

 of 1907 as many pullets as possible from "200-egg" hens and 

 keep an exact pedigree record on the mother's side of each of 

 these chickens, x^n exact pedigree record of the male ancestry 



* Papers from the Biological Laboratory of the Maine Agricultural 

 Experiment Station. No. lo. 



This paper forms No. II of a series of "Studies on the Physiology 

 sof Reproduction in the Domestic Fowl." No. I of the series has the 

 subtitle "Regulation in the Morphogenetic Activity of the Oviduct" and 

 is published in the Journal of Experimental Zoology. Vol. 6. 



