A PHYSIOLOGICAL CHARACTER. 



81 



lines (29 months), representing 95 generations in the plus and 91 

 generations in the minus strain. The data are given in tables 37 

 and 38 and figure 13. 



The courses of the reaction-time curves are extremely irregular, 

 although in a general way the curves follow each other in a manner 

 to suggest environmental influence upon reaction-time. It is obvious 

 that there was no effect of selection. 



TABLE 37. Selection summary for Line 796. 



Time period. 



Dec. 25, 1914- 



July 31, 1915 

 Aug. 1, 1915- 



July 31, 1916 

 Aug. 1, 1916- 



May 1, 1917 

 Test series, 



Aug. 1916. . . 

 July 1, 1916- 



Sept. 30, 1916 



Strair 



Plus.... 

 Minus . . 

 Plus.... 

 Minus . . 



Plus 



Minus . . 



Plus 



Minus . . 



Plus 



Minus . . 



1-28 



1-27 



28-61 

 67-95 



65-71 



12.3 



27 13.0 

 38 15.9 

 33 8.0 

 22 13 

 SO 

 2033.1 



619.1 

 697.6 

 449.4 

 393.7 

 675.6 

 653.7 

 662.4 

 453.8 



289.5 

 290.9 

 291.9 

 297.2 

 331.1 

 311.9 

 286.6 

 302.8 

 201.3 

 319.9 



10.5 

 10.5 

 8.0 

 12. 3 

 12.8 



8.1 

 12.6 

 21.7 



-43.3 



-78.4 

 +55.7 



+21. 



fi 



14.93.31 

 14.76'.3S 



TABLE 38. Same-day broods. Summary of data for Line 796. 



Time period. 



Dec. 25, 1914- 

 July 31, 1915 



Aug. 1, 1915- 

 July 31, 1916 



Aug. 1, 1916- 

 May 1, 1917 



Strain. 



Plus... 

 Minus . 

 Plus. .. 

 Minus . 

 Plus. .. 

 Minus . 



I 



634 

 523 

 674 

 680 

 723 

 503 



283.10 

 281.80 

 176.68 

 898.67 

 291.84 

 303.64 



24.86 +111 



10.11 

 21.84 

 23.87 

 SB. 7 9 



is 



n 



+220 



The mean reaction-times for the first longer period (8 months) 

 of the experiment were 555.5 and 604.8 seconds, the plus strain 

 being the more reactive by a margin of 49.3 14.9 seconds, a differ- 

 ence 3.31 times the probable error (table 37). The 7 same-day 

 broods for this period gave averages indicating greater reactiveness 

 for the minus strain by a difference of +111 36. 23 seconds, more 

 than double the difference obtained from the entire data for this 

 period and in the reverse direction (table 38). 



