The Three Dagger-thrusts 



fallibility and the intuitive science of instinct 

 appear in all their splendour. Let us first 

 recall the principal conclusions to which our 

 earlier study of the Cerceris has led us. 

 The victims of the Wasps whose larvae live 

 on prey are not proper corpses, in spite of 

 their immobility, which is sometimes com- 

 plete. They suffer simply from a total or 

 partial locomotory paralysis, from a more or 

 less thorough annihilation of animal life; 

 but vegetable life, the life of the organs of 

 nutrition, is maintained for a long while yet 

 and preserves from decomposition the prey 

 which the larva is not to devour for some 

 time to come. To produce this paralysis, 

 the Hunting Wasp employ precisely the 

 process which the advanced science of our 

 own day might suggest to the experimental 

 physiologists, that is to say, they injure, by 

 means of their poisoned sting, the nerve- 

 centres that control the locomotory organs. 

 We know besides that the several centres or 

 ganglia of the nervous system of articulate 

 animals are, within certain limits, independ- 

 ent of one another in their action, so that an 

 injury to any one of them does not, or at 

 any rate not immediately, entail more than 

 the paralysis of the corresponding segment; 

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