BEHAVIOR OF THE ANT-LION. 



301 



and six-tenth minutes. (4) This death-feigning cannot be in- 

 definitely prolonged. (5) The duration of the feints near the 

 end of a long series of trials is always shorter than that of the 

 earlier ones. (6) A curve representing the relative lengths of a 

 series of letisimulations always contains two or more crests. 

 (7) The longest feints usually occur somewhere near the beginning 

 of the series. Of the 100 cases recorded, 33 letisimulated longest 

 on the first trial, ti on the second, 15 on the third, 2 on the 

 fourth, 5 on the fifth, 7 on the sixth, 3 on the seventh, 5 on the 

 eighth, 6 on the ninth, 5 on the tenth, I on the eleventh, 4 on the 

 twelfth, 2 on the thirteenth, and I on the sixteenth. We have 

 here, in a pronounced manner, the irregularity noticed by the 

 Severins and Gee and Lathrop in the forms studied by them. 



Effects of Temperature upon the Duration of Letisimulations. 

 To test this matter the TOO individuals mentioned were grouped 

 according to the temperatures at which the experiments had been 

 performed, and the tesults recorded in six tables. From the 

 averages of those tables the following table was compiled. 



TABLE SHOWING THE AVERAGES OF THE EFFECT OF TEMPERATURE ON THE 



LETISIMULATIONS. 



If we were to rely upon these averages, we would conclude that 

 up to 75 F. both the length of the maximum feint and the total 

 duration of twenty feints vary directly with the temperature; 

 and that beyond that point there is no definite relation between 

 temperature and the feints. This conclusion, however, is not 

 supported by a critical study of the individual records from which 

 the averages were compiled. To test the matter further, four 

 individuals were selected and each put through five series of 

 twenty letisimulations, each series being conducted at a different 

 temperature. The results were recorded in four tables. There 



