EVIDENCE OF GERM CELL SELECTION 393 



takable, was nevertheless remarkably slight considering the 

 strength of the treatment. It should be noted in passing that 

 there is the possibility of a mild degree of asphyxiation, but 

 this probably is of no importance in the present connection. 



The five hens used in experiment 4 were affected much more 

 severely. They were commonly completely overcome and 

 entirely unable to stand for several minutes after being released 

 from the inhalation chamber. Staggering, which was rarely 

 noticeable in the males, was of regular occurrence with these 

 females. Despite precautions taken to the contrary, all but 

 one of them ultimately died from the effects of the treatment. 

 The one remaining individual developed, or had inherently, a 

 considerable power of resistance. 



Aside from the immediate but transient effects of the alcohol, 

 nothing was noted except a slight loss in weight. For example, in 

 the fifty-seven days from February 9 to April 7 no. 28 (treated), 

 with an initial weight of 1803 grams lost 133 grams, while in 

 the next fifty-seven days no. 28 (untreated) gained 160 grams, 

 and no. 27 (treated) fell from 1825 grams to 1695 grams, a loss 

 of 130 grams. 



DESCRIPTION OF THE EXPERIMENTS 



The method of administering the alcohol and the general 

 character of the obvious physiological responses have already 

 been indicated. It remains only to outline the special features of 

 the individual experiments, of which a condensed summary is given 

 in tables 1 and 2. The control period preceded the period of 

 treatment in experiments 1, 2 and 4, but in experiment 3 this 

 relation was reversed. The surroundings and care of all the 

 flocks during both A and C periods were made as constant as pos- 

 sible. Eggs were put in the incubator in all cases, except 1-C, 

 twice weekly and on definite days, so that no egg had been laid 

 more than four days when incubation commenced. 



Experiment 1 . (February 15, 1917 to June 2,-1917). Thehetero- 

 zygous parent (male no. 8) was raised at the laboratory from 

 mongrel ancestors. His mother (no. 6), w^as a monster of the 



