TI4 MAINE AGRICULTURAL EXPERIMENT STATION. I9II. 



5. Studies on Hybrid Poultry. Maine Agr. Expt. Stat. Ann. 

 Rp-t. for 1910, pp. 84-116, 1910. (Pp. 100-106 deal with fecun- 

 dity). 



6. The Relation of the Results Obtained in Breeding Poul- 

 try for Increased Egg Production to the Problem of Selection. 

 Rpt. 30th Meeting Soc. Proc. Agr. Sci. pp. (of reprint) i-8. 



7. Inheritance in "Blood Lines" in Breeding Animals for 

 Performance, with Special Reference to the "200-Egg" Hen, 

 Ann. Rpt. Amer. Breeders Assoc. Vol. VI, pp. 317-326, 191 1. 



8. Inheritance of Fecundity in the Domestic Fowl. Amer. 

 Nat. Vol. XLV. pp. 321-345, 191 1. (This paper is reprinted 

 in full as Part IV of the present bulletin). 



9. Biometric Arguments Regarding the Genotype Concept. 

 Amer. Naturalist, Vol. XLV, pp. 561-566, 191 1. 



Most of these papers cited above deal with certain essentially 

 negative results obtained in the earlier years of the experiments. 

 It seems desirable, as an introduction to the positive results now 

 reported, to review briefly the entire history of the work at the 

 ]\Iaine Station in the experimental breeding of poultry with 

 reference to the character fecundity or egg production. Another 

 reason for publishing the present bulletin lies in the fact that 

 most of the i3apers in which the original data and results have 

 been presented are not easily accessible to the agricultural pub- 

 lic. It is hoped that this bulletin may help to meet the demand 

 for information on the part of that j)ublic in regard to the 

 progress of the breeding work at the Maine Station. Finally it 

 is desired to present at this time some data not hitherto pub- 

 lished regarding obscure and doubtful points of interpretation 

 and suggested criticisms of the experiments in breeding. 



For detailed evidence on any point discussed, except such as 

 are here presented for the first time, the reader is referred to 

 the original papers listed above. 



PLAN OP EARLIER WORK. 



The earlier work of the Station on this subject, which cov- 

 ered the years 1898 to 1907 inclusive, was concerned, and exe- 

 cuted in conformity, with the then prevailing views respecting 

 the effectiveness of mass selection. The underlying idea which 

 dominated these earher experiments was that by breeding con- 

 sistently year after year from the highest layers, regardless of 



