The Modern Theory of Instinct 



sence of her caterpillar, there was nothing, 

 you would have it, to guide the sting. The 

 choice was made at random. The pricks 

 were directed at the upper surface of the cap- 

 tured prey, at the lower surface, at the sides, 

 the front and the back indiscriminately, ac- 

 cording to the fortunes of a close struggle. 

 The Hive-bee and the Social Wasp sting 

 those points which they are able to reach, 

 without showing a preference for one part 

 over the other. That is how the Ammophila 

 must have acted, when still ignorant of her 

 art. 



Now how many points are there in a Grey 

 Worm, above and below? Mathematical 

 accuracy would answer, an infinity; a few 

 hundreds will serve our purpose. Of this 

 number, nine or perhaps more have to be 

 selected; the needle must be inserted there 

 and no elsewhere: a little higher, a little 

 lower, a little to one side, it would not pro- 

 duce the desired effect. If the favourable 

 event is a purely accidental result, how many 

 combinations would be needed to bring it 

 about, how much time to exhaust all the pos- 

 sible cases? When the difficulty becomes 

 too pressing, you take refuge behind the mist 

 of the ages; you retreat into the shadows of 

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