Holmes, Death-feigmng in Ranatra. 209 



EXPERIMENT i. 



Under Moving Light. Under Stationary Light. 



3 2° 



4 28 

 8 40 



15 41 



26 42 



Average 11.2 minutes. .Average 34.2 minutes. 



EXPERIMENT 2. 



Under Moving Light. Under Stationary Light. 



13 

 3 H 



3 IS 



6 21 



II 24 



15 38 



21 39 



21 78 



Average 11. 4 minutes. Average 30.2 minutes. 



Specimens that have been lying quiet for some time may fre- 

 quently be aroused very quickly if the light is moved about near 

 them. Each time the light approaches they respond with a twitch 

 which increases in vigor with each repetition until finally they 

 get up and begin to walk around. 



DEATH-FEIGNING IN DECAPITATED SPECIMENS. 



In cutting off the head of Ranatra close to the body only the 

 supraesophageal ganglion is removed. The subesophageal 

 ganglion lies considerably behind its usual position in the insects 

 and is closely connected with the first ganglion of the thorax so 

 that it cannot easily be destroyed without inflicting injury to the 

 latter organ. In each case the head of the decapitated specimen 

 was examined to make sure that the supraesophageal ganglion 

 (which also lies quite far back) was entirely extirpated. 



