XI THE SCIENCE OF INSTINCT 153 



from the Sphex, who, without having learned, with- 

 out ever seeing any one else at work, is thoroughly up 

 in her profession of operator. She knows that under 

 her victim's skull lies a circlet of nerve-knots, somewhat 

 analogous to the brain of higher animals. She knows 

 too that this chief nerve centre directs the action of 

 the mouth-parts, and, moreover, is the seat of will, with- 

 out whose command no muscle acts ; finally, she is 

 aware that if this kind of brain be injured, all re- 

 sistance will cease, the insect no longer possessing 

 will-power. As for the method of operation, it is 

 the easiest thing possible for her, and when we have 

 studied at her school we may try in our turn. The 

 sting is no longer employed ; in her wisdom the 

 Spex decides compression to be preferable to the 

 poisoned sting. Let us bow to her decision, for we 

 shall presently see how prudent it is to be convinced 

 of our ignorance compared with the animal's know- 

 ledge. Lest by re-writing my account I fail to do 

 justice to the sublime talent of this masterly opera- 

 tion, I transcribe my notes written on the spot 

 directly after witnessing the exciting spectacle. 



The Sphex, finding that her prey resists too much, 

 hooking itself here and there to blades of grass, 

 pauses to perform the singular operation about 

 to be described — a kind of coiip de grace. The Hy- 

 menopteron, still astride her victim, makes the 

 articulation in the upper part of the neck, at the 

 nape, to open wide. Then she seizes the neck with 

 her mandibles, groping as far forward as possible 

 under the skull, but making no outward wound, grasps 

 and chews repeatedly the nerve-centres of the head. 

 This renders her victim quite motionless, and incapable 



