214 'Journal of Comparative Neurology and Psychology. 



independently. The effect of cutting the nerve cord in the 

 prothorax is greatly to lessen the spontaneous movements of the 

 second and third pairs of legs. The posterior legs may move 

 about when the head and anterior legs are quiet and vice versa. 

 When the whole insect is caused to feign the posterior part is 

 usually the first to recover, although it does not always give 

 such evident signs of so doing. 



DECEPTIVE QUIET. 



It was onlv after keeping Ranatras for some time that I ob- 

 served that they manifested the least awareness of my presence. 

 So far as observed these insects never attempt to escape by swim- 

 ming or walking away, although other aquatic hemiptera, such 

 as Zaithas, water boatmen, etc., make a great ado upon one's 

 approach and scurrv away in the most lively manner. So un- 

 gainly an insect as Ranatra could seldom effect its escape by 

 swimming, much less by walking, from any enemy large enough 

 to overpower it. And when out of water it apparently never 

 occurs to the poor creature to seek to get away by using its wings, 

 although it could often easily do so. Ranatra seems to be entirely 

 devoid of all instincts to seek safety by flight in ever)^ sense of this 

 term. In experimenting on the reactions of these forms to light 

 I have worked with individuals for hours, picking them up here 

 and setting them down there, and subjecting them to a variety 

 of treatment some of which was perhaps not particularly pleasant, 

 yet the creatures seemed stolidly unaware of my existence except 

 when actually handled. Pick up a Ranatra that is bent on going 

 to the light, and if it does not feign death it will travel to the light 

 immediately after being Hberated as if impatient of the rude 

 interruption. I have often observed individuals struggle to get 

 to the light even before their release. If its phototactic pro- 

 clivities are well aroused one may make all sorts of movements 

 in the vicinity of a Ranatra that is seeking the light but the insect 

 will completely ignore them. 



Ranatras under natural conditions are nevertheless keenly 

 aware of the events that take place in their neighborhood. They 

 are attracted by small moving objects that may serve for prey, 

 and these they lie in readiness to seize. The appearance of large 

 objects in their field of vision causes a sudden and complete 



