The Cetonia-larva 



the animal uncoils like a broken spring. 

 Henceforth motionless, it lies on its back, 

 its ventral surface fully exposed from end 

 to end. On the median line of this surface, 

 towards the rear, near the brown patch due 

 to the alimentary broth contained in the in- 

 testine, the Scolia lays her egg and without 

 more ado, leaves everything lying on the 

 actual spot where the murder was committed, 

 in order to go in search of another victim. 



This is how the deed must be done: the 

 results prove it emphatically. But then the 

 Cetonia-grub must possess a very exceptional 

 structure in its nervous organization. The 

 larva's violent contraction leaves but a single 

 point of attack open to the sting, the under 

 part of the neck, which is doubtless unco- 

 vered when the victim tries to defend itself 

 with its mandibles; and yet a stab in this one 

 point produces the most thorough paralysis 

 that I have ever seen. It is the general 

 rule that larvae possess a centre of innerva- 

 tion for each segment. This is so in part- 

 icular with the Grey Worm, the sacrificial 

 victim of the Hairy Ammophila. The Wasp 

 Is acquainted with this anatomical secret: 

 she stabs the caterpillar again and again, 

 from end to end, segment by segment, gan- 

 glion by ganglion. With such an organiza- 

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