Holmes, Death-jeigmng in Ranatra. 201 



circumstances, however, the feint does not usually last for more 

 than an hour. There is a wide variability in the duration of the 

 feint in different individuals under the same conditions; and differ- 

 ent circumstances, as will be described below, influence the result 

 to a very marked degree. 



The death feint may be brought about by picking the insect up 

 in the fingers, or, if this does not suffice, by gently stroking the 

 body. If an individual that is picked out of the water persists in 

 moving its legs about in an effort to escape, it may usually be quiet- 

 ed if its legs are bent backward alongside the abdomen and the 

 body gently stroked or rolled about in the fingers. If when begin- 

 ning to come out of its feint Ranatra is stroked or sometimes even 

 lightly touched it will resume feigning. A breath of air blown 

 upon the insect will frequently produce the same result. When 

 Ranatra is walking about it often happens that, owing to the lack 

 of adequate support by the legs, the body is allowed to touch the 

 table. This contact frequently results in causing the insect 

 suddenly to feign death for several minutes. The death feint 

 may be induced in susceptible individuals by slight contact upon 

 the thorax, legs or abdomen. Contact with the breathing tube, 

 however, is much less likely to produce this result. In handling 

 specimens which I do not wish to throw into the death feint I find 

 that it is best to seize them by the tip of the breathing tube. 

 Specimens may be moved about in this way and still kept in an 

 active condition, whereas they would be pretty certain to feign 

 death if they were seized by any other part of the body. If they 

 can be induced to use their legs and walk off before their body 

 comes in contact with the table they are much less apt to feign. 

 This may be frequently accomplished by dragging them back- 

 ward over the top of the table so that their claws catch in the wood. 

 The walking reflexes are thus set up and the insect may often be 

 picked up in one place and set down in another without throwing 

 it into a quiescent state. 



While in the death feint Ranatra is in a condition of tetanus. 

 The muscles are set so that the body and limbs are in a state of 

 extreme rigidity. All sorts of unnatural positions which the insect 

 may happen to assume in the beginning of the feint are retained 

 for a long period. It may be picked up by the outstretched 

 anterior legs and held out straight, ventral side upwards, for some 

 time without bending the legs. When the weight of the insect 



