A PHYSIOLOGICAL CHARACTER. 



87 



random. Because of this fact, the data for 4 months (October 1916- 

 January 1917) are not very complete and the differences for those 

 2 two-month periods are not to be credited to the same extent as 

 the differences for the remainder of the experiment. 



Reference to tables 48 and 49 (columns 5 and 6) and figure 15 

 and 18b shows that this consistent divergence in reactiveness be- 



2.00 



1.50 



1.00 - 



50 



00 





t 



u 



^ ? J 



s - 



-2 



8-9 12-1 A-5 8-9 I2-I 4-5 8-9 12- 

 1912 1913 1914 



4-5 8-9 12-1 4-5 8-9 12-1 4 



1915 1916 1917 



Figure 14. — ^Line 740. 

 A. Reproductive indices, actual values. B. Reproductive indices, superiority. 



900 



750 



600 



450 



300 



150 



00 



8-9 12-1 4-5 8-9 12-1 4-5 8-9 12-1 4-5 8-9 12-1 4-5 8-9 12-1 4 

 1912 1913 1914 1915 1916 1917 



I 



Figure 15. — Line 740. 

 Reaction-time curves with reaction-time curves for Line 757 superimposed. 



