The Great Cerceris 31 



second pair of legs and lastly those of the third 

 pair hasten to do likewise. Once movement 

 sets in, these different appendages execute their 

 vibrations without any order, until the whole 

 relapses into immobility, which happens more 

 or less quickly. Unless the blow has been dealt 

 quite recently, the motion of the tarsi extends 

 no farther and the legs remain still. 



Ten days after an attack I was unable to 

 obtain the least vestige of susceptibility by the 

 above process ; and I then had recourse to 

 the Voltaic battery. This method is more 

 powerful and provokes muscular contractions 

 and movements where the benzine-vapour fails. 

 We have only therefore to apply the current 

 of one or two Bunsen cells through the con- 

 ductors of some slender needles. Thrusting the 

 point of one under the farthest ring of the 

 abdomen and the point of the other under the 

 neck, we obtain, each time the current is estab- 

 lished, not only a quivering of the tarsi, but a 

 strong reflexion of the legs, which draw up 

 under the abdomen and then straighten out 

 when the current is turned off. These flutter- 

 ings, which are very energetic during the first 

 few days, gradually diminish in intensity and 

 appear no more after a certain time. On the 

 tenth day I have still obtained perceptible 

 movements ; on the fifteenth day the battery 



