194 ^^^ Htmting Wasps 



or barely touched the fifth ration. If four 

 Crickets are necessary to the larva to acquire the 

 full development called for by its organization, 

 why are sometimes only three, sometimes only 

 two provided for it ? WTiy this enormous 

 difference in the quantity of the victuals, some 

 larvae having twice as much as the others ? 

 It cannot be because of any difference in the 

 size of the dishes provided to satisfy the grub's 

 appetite, for all have very much the same 

 dimensions ; and it can therefore be due only 

 to the wastage of game on the way. We 

 find, in fact, at the foot of the banks whose 

 upper stages are occupied by the Sphex-wasps, 

 Crickets that have been paralysed but lost, 

 owing to the slope of the ground, down which 

 they have slipped when the huntresses have 

 momentarily left them, for some reason or 

 other. These Crickets fall a prey to the Ants 

 and Flies ; and the Sphex-wasps who come 

 across them take good care not to pick them up, 

 for, if they did, they would themselves be 

 admitting enemies into the house. 



These facts seem to me to prove that, while 

 the YeUow-winged Sphex' arithmetical powers 

 enable her to calculate exactly how many 

 victims to capture, she cannot achieve a 

 census of those which have safely reached their 

 destination. It is as though the insect had no 



