88 Studies in Animal Behavior 



became quiet it could generally be caused to resume 

 its activity by pulling it slightly backwards. In 

 both Pieris and Melitaea the head was kept turned 

 slightly toward the light. Eurymus eurytheme and 

 Caenonympha californica also rotated the disk away 

 from the light. Most of the specimens of Euva- 

 nessa antiopa experimented with failed to give re- 

 sults on account of feigning death so long as they 

 were held, but one individual became active after 

 a time and consistently rotated the disk away from 

 the illuminated side. 



"Two species of Diptera of the family Tachinidae 

 rotated the disk uniformly away from the light. 

 Other specimens when held would execute only ir- 

 regular movements. The same was true of several 

 other phototactic insects belonging to different or- 

 ders. The aculeate Hymenoptera expended most of 

 their energy in efforts to sting their captor; and 

 attempts to escape in most other cases effectually 

 overcame any phototactic proclivity that may have 

 existed. However, the comparatively few insects 

 that continued to exhibit light reactions under the 

 unnatural condition of being held between the fin- 

 gers or by forceps gave such uniform and unequivo- 

 cal reactions that there can be little doubt that 

 light exercised a continuous stimulating influence 

 upon their activity. The slight movements due to 

 one's hand or the insect's own actions would affect 

 but very little the amount of stimulation received 

 by the eye, and whatever effects would be produced 



