46 



observations made upon the twenty-eight generations 

 while they were subjected to the influence of the alcohol. 

 One can not compare strictly the number of individuals in 

 the different generations because of the changed condi- 

 tions, especially of the temperature, and in some instances 

 the length of time between the generations. However, 

 the ratios between the strains or groups in all the genera- 

 tions maybe compared and will show general uniformity. 

 The first few generations of the ^ per cent., and the i per 

 cent, alcoholic strains show a fluctuation in the rate of 

 reproduction above and below that of the control ; but this 

 rate of reproduction in the I per cent, alcoholic strain 

 never rises to that of the control after the sixth genera- 

 tion. In the £ per cent, alcoholic strain the rate of repro- 

 duction never rises to that of the control after the third 

 generation. In the 1 per cent, alcoholic strain the rate 

 of reproduction even in the first generation does not equal 

 that of the control. The summary shows in the average 

 number of offspring for each female that the alcoholic 

 strains differ in the rate of reproduction according to the 

 amount of alcohol used. The more alcohol used the lower 

 the rate of reproduction. 



Another test to show the influence of the 1 per cent, 

 alcohol in this same series was made by removing some of 

 the individuals from the alcoholic solution and placing 

 them in a 1/14,000 G. M. copper sulphate solution 2 and 

 comparing the resisting power, or the ability to live, of 

 this strain with that of the control when both were sub- 

 jected to the copper sulphate solution. Table II shows 

 the detailed data and Table III shows the summary. In 

 the control 96.8 per cent, of the individuals lived forty- 

 eight hours and produced young, while only 15 per cent, 

 of the individuals taken from the 1 per cent, alcoholic 

 strain in the XIII-XV generations lived forty-eight hours 

 and produced young. This shows that the susceptibility 

 to copper sulphate is greatly increased by the alcohol. 



was selected because it appeared to be of the maximum strength which the 

 control could withstand. 



