Under 30 



Zero 



7i 



V 



7:5 







INHERITANCE OE EECUNDITY IN DOMESTIC EOWL. 323 



All 2 Progeny 



Winter Production: Over so 



Observed 102 



Expected 11.5 



Mean winter production 49.80 eggs 15.71 eggs o eggs 



The zero bird here is an exception for which no apparent ex- 

 planation is forthcoming. She was not pathological. She was 

 however a June hatched bird. Unfortunately she was not bred, 

 and therefore it is not possible to be sure of her gametic con- 

 stitution. In spite of the fact that the total number of progeny 

 here is small, there is little doubt of the correctness of the clas- 

 sitication. 



The mean productions for birds in the 'Over 30' class in the 

 several matings are comparatively a little lower than those of 

 the progeny of other class 7 males. It is interesting to specu- 

 late as to whether this may be connected with the lack of great 

 vigor on the part of the sire. No data are available from which 

 to get critical evidence on this point. 



B.P.R. $ j6. Indicated constitution =: fUL^. fUL'z. 



This bird was purchased in January, 1908, from Air. C. H. 

 Welles of Stratford, Conn. It came from a strain of Barred 

 Rocks well known in the show-room, but not specially bred for 

 egg production. This fact is of interest in connection with the 

 breeding history of the bird, which indicates clearly that he 

 was homozygous with respect to L2. The result shows, in other 

 words, that a male Barred Rock from a strain bred purely for 

 the fancy may still carry in pure form the factor for high egg 

 production. 



This male bird (56) was bred two seasons (1908 and 1909). 

 The first year he got but very few adult daughters, owing to 

 the unfavorable conditions under which all the breeding had to 

 be done in 1908 (cf. Pearl and Surface 35.) In 1909 the results 

 were better. The adult daughters from both seasons are taken 

 together in the following breeding history. 



