g6 INSECT LIFE vn 



movement can turn the sting from the points where 

 the drop of poison must be instilled, and probably 

 it is in order to hinder any motion of the abdomen 

 that one of the end segments is grasped. If a fertile 

 imagination had had free play to invent a plan of 

 attack it could not have devised anything better, 

 and it is questionable whether the athletes of the 

 classic palestra when grappling an adversary would 

 have assumed attitudes more scientifically calculated. 

 I have just said that the dart is plunged several 

 times into the victim's body, once under the neck, 

 then behind the prothorax, lastly near the top of the 

 abdomen. It is in this triple blow that the in- 

 fallibility, the infused science of instinct, appear in 

 all their magnificence. First let us recall the chief 

 conclusions to which the preceding study of the 

 Cerceris have led us. The victims of Hymenoptera 

 whose larva live on prey are not corpses, in spite of 

 entire immobility. There is merely total or partial 

 paralysis, and more or less annihilation of animal life, 

 but vegetative life — that of the nutritive organs — lasts 

 a long while yet, and preserves from decomposition the 

 prey which the larvae are not to devour for a con- 

 siderable time. To produce this paralysis the pre- 

 datory Hymenoptera use just those methods which 

 the advanced science of our day might suggest to the 

 experimental physiologist — namely, wounding, by 

 means of a poisoned dart, those nervous centres which 

 animate the organs of locomotion. We know too 

 that the various centres or ganglia of the nervous 

 chain in articulate animals act to a certain degree 

 independently, so that injury to one only causes, at 

 all events immediately, paralysis of the corresponding 



