VII THREE STROKES OF A DAGGER 97 



segment, and this in proportion as the ganglia are more 

 widely separated and distant from each other. If, on 

 the contrary, they are soldered together, injury to the 

 common centre causes paralysis of all the segments 

 where its ramifications spread. This is the case 

 with Buprestids and Weevils, which the Cerceris 

 paralyses by a single sting, directed at the common 

 mass of the nerve centres in the thorax. But open 

 a cricket, and what do we find to animate the three 

 pairs of feet ? We find what the Sphex knew long 

 before the anatomist, three nerve centres far apart. 

 Thence the fine logic of the three stabs. Proud 

 science ! humble thyself. 



Crickets sacrificed by Sphex flavipennis are no more 

 dead, in spite of all appearances, than are Weevils 

 struck by a Cerceris. The flexibility of the integuments 

 displays theslightest internal movement,and thus makes 

 useless the artificial means used by me to show some 

 remains of life in the Cleonus of Cerceris tuberculata. 

 If one closely observes a cricket stretched on its back a 

 week or even a fortnight or more after the murder, one 

 sees the abdomen heave strongly at long intervals. 

 Very often one can notice a quiver of the palpi and 

 marked movements in the antennae and the bands of 

 the abdomen, which separate and then come suddenly 

 together. By putting such crickets into glass tubes 

 I have kept them perfectly fresh for six weeks. 

 Consequently, the Sphex larvae, which live less than a 

 fortnight before enclosing themselves in their cocoons, 

 are sure of fresh food as long as they care to feast. 



The chase is over ; the three or four crickets 

 needed to store a cell are heaped methodically on 

 their backs, their heads at the far end, their feet 



H 



