156 



EAYMOND PEARL 



D. Time of beginning treabnent 



The inhalation treatment was started on the different birds 

 at different dates. This was done in order to determine whether 

 the length of time they had been treated prior to entering upon 

 the breeding season would make any difference in their per- 

 formance as breeders in the breeding season of 1915. The data 

 regarding the beginning of the experimental treatment of the 

 different birds are set forth in table 4, which requires no fuither 

 explanation. 



TABLE 4 

 Showing the dates of beginning of alcohol treatment 



E. Plan of matings in 1915 



The alcohohzed birds and the untreated controls were mated 

 early in February, 1915. Eggs were saved for incubation from 

 these matings from about February 15. The general methods 

 of handling these matings, incubation, brooding the chicks, etc., 

 were the routine methods followed in the WTiter's breeding ex- 

 periments with poultry. Long experience has proved these 

 methods to be excellently adapted to the rearing of normal 

 healthy chicks. They are described by Pearl (22). 



During incubation and brooding, indeed throughout life, the 

 eggs and chicks from these alcohol experiments were not sepa- 

 rated from the general flock. In other words, the eggs from 

 these experiments were put at the same time in the incubators 



