260 Annals Entomological Society of America [Vol. XIV, 
It is evident, from the observations and experiments of these 
and other writers, that responses to contact stimuli are closely 
associated with the death-feint. Holmes (1906, pp. 200-201, 
206, 211) has pointed out the fact that contact and stroking 
the bodies of Ranatras with the fingers induces the death- 
feint. He (1906, p. 204) records the interesting observation 
that when the water-scorpions arouse from the response, the 
death-feint again can be invoked by contact. This writer 
(1906, p. 201) also declares that the contact of air currents 
brings about the death-feigning response. According to Holmes 
(1907, pp. 161-163), Ranatra quadridentata exhibits the death- 
feigning response. He found that the response is not so pro- 
nounced in young Ranatras as is the case in older individuals. 
Contact stimulation appears to be influential in eliciting the 
response both in the immature and adult insects. Under 
certain conditions, as the water-scorpions arouse from the 
death-feint, it can be induced again by contact stimuli. 
In the interesting monograph by Severin and Severin 
(1911, p. 2), the fact is pointed out that Belostoma flumineum 
feigns death ‘‘ when raked or scooped out of the water.’’ Picking 
it ‘‘out of the water from an aquarium,’’ or repeated contact 
of the fingers to the abdomen, often elicits the death-feigning 
response. Nepa apiculata readily feigns death, while in the 
water, if it is touched on the dorsal side “with a pencil or other 
object.’’ A similar response is obtained by removing the 
insect from the water by means of a pair of forceps. The result 
is the same, whether it is grasped by the body, the breathing 
tube, or the legs. It is evident, in these instances, that contact 
stimulation is the factor which induces the death-feint. These 
writers (1911, pp. 6, 7) direct attention to other examples of the 
influence of contact stimuli in eliciting the death-feigning 
response. Nepa apiculata will feign death when placed on its 
back. After arousing from the death-feint it attempts to turn 
over onto its ventral side and in making such an attempt the 
animal often falls again onto its back. The effect of the shock, 
in falling back again, may result in inducing the response. 
When righting itself, the “‘shock effect’’ of dropping onto its 
ventral surface is frequently sufficient to elicit the death-feint. 
A feigning Belostoma flumineum can be aroused by a breath of 
air blowing against it. The contact of a pair of forceps, a 
house-fly, or another Belostoma, any one of these, may stimulate 
