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C. H. TURNER 



tion ; but in no case did the wasp drop backwards or turn through 

 an angle of 180 degrees. 



Two experiments were performed, one on the seventh and 

 the other on the tenth of June, 191 1. In each experiment, at 

 intervals, the position of each wasp was noted. The results of 

 those observations are recorded in the following two tables. 



In each of the tables of this article, the number at the 

 top of a column indicates the time when the observation was 

 made. "Li." stands for "In the light," and "Sh." means "In 

 the shadow." 



Experiment 1, June ?th, 12 wasps involved. 



Wasps resting on or hovering near the 



east side of the cage . 

 west side of the cage 

 roof of the cage .... 

 floor of the cage. . . . 

 other two sides 



Total 



8:30 



Li. Sh. 



8:40 



Li. Sh 



Experiment 2, June 10th, a. m., from 18 to 28 wasps involved.* 



2 Wasps resting in or under the mud cells were not counted. Since the number 

 of wasps so situated varied from time to time, the number of wasps in the experi- 

 ment was not uniform. 



SERIES II 



In this series the stimulus was direct sunlight. The general 

 arrangement was the same as in series I ; but an opaque screen 

 nine inches long and six wide was placed over some portion of 

 the east side of the cage. 



