The PVisdom of Instinct 169 



the food which the larvae appreciate above all 

 others. My suspicion is well founded ; de- 

 prived of her capture, the Sphex stubbornly 

 refuses the male whom I offer to her. She runs 

 hither and thither, with hurried steps, in search 

 of the vanished game ; three or four times she 

 goes up to the Ephippiger, walks round him, 

 casts a scornful glance at him ; and at last she 

 flies away. He is not what her larvae want ; 

 experiment demonstrates this once again after 

 an interval of twenty years. 



The three females stabbed, two of them 

 before my eyes, remain in my possession. In 

 each case all the legs are completely paralysed. 

 Whether lying naturally, on its belly or on its 

 back or side, the insect retains indefinitely 

 whatever position we give it. A continued 

 fluttering of the antennae, a few intermittent 

 pulsations of the belly, and the play of the 

 mouth-parts are the only signs of life. Move- 

 ment is destroyed but not susceptibility ; for, 

 at the least prick administered to a thin-skinned 

 spot, the whole body gives a slight shudder. 

 Perhaps, some day, physiology will find in such 

 victims the material for valuable work on the 

 motions of the nervous system. The Wasp's 

 ing, so incomparably skilful at striking a par- 

 ticular point and administering a wound which 

 affects that point alone, will supplement, with 



