The Instinct of Feigning Death 2il 



time, and Belostoma, in exceptional cases, may feign 

 for as much as a few minutes. Throwing any of 

 these insects into water while they are feigning usu- 

 ally terminates the feint at once or in a short time. 

 The transition from air to water, even when no 

 temperature changes are encountered, produces a 

 marked effect on the reactions of many semi-aquatic 

 forms. In Ranatra and certain terrestrial amphi- 

 pods, as we have seen in a previous chapter, it pro- 

 duces a sudden reversal of phototaxis, a change not 

 improbably due to the influence of contact stimuli. 

 It is not improbable that it is the influence of con- 

 tact stimulation that terminates the death feint of 

 aquatic bugs when they are placed in the water. 

 Most insects and crustaceans which feign can be 

 caused to do so repeatedly by stroking or handling 

 them as soon as they show signs of activity. I 

 have performed a number of experiments on amphi- 

 pods, Ranatra, beetles and orb-weaving spiders to 

 ascertain how long the death feint may be continued, 

 and to determine also the lengths of successive feints. 

 In all the forms experimented with there was found 

 to be much variability in the behavior of different 

 individuals, so that it was necessary to perform 

 numerous experiments in order to arrive at trust- 

 worthy conclusions. In general, all the forms stud- 

 ied showed a gradual diminution in the duration of 

 successive feints, until, often after several hours, 

 it was no longer possible to evoke the response. 

 Similar experiments undertaken at my request by the 



