174 



RAYMOND PEARL 



reasonable to conclude that the inhalation treatment had very 

 httle if anything to do with causing it. 



2. The male birds show the same initial rise in body weight 

 as do the females. Unfortunately we have no control figures 

 for the males, but in all probability the same considerations 

 hold for them as for the females just discussed. 



2000 



1800 



1600 



1200 



[Fig. 2 Diagram showing the changes in body weight of males subjected to 

 the inhalation treatment. The lines have the same significance as in figure 1. 

 All plottings are on the basis of single individuals not means. 



3. Following the initial rise, which reaches its peak in Janu- 

 ary or February, there is a sharp and prolonged fall in body 

 weight which reaches its lowest point in either May or June, 

 in the case of the females and a month or two months later in 

 the case of the males 664 and 665. The absolute amount of 

 this loss in body weight is large, particularly in the females. In 

 it is probably to be seen the first significant effect of the con- 

 tinued administration of the poisons. Just as before, it is im- 



