The Mason-Wasps 



a kick or two, they find nothing in front of 

 them: the Ammophila's egg is in the op.- 

 posite direction. The httle grub is thus 

 able, as soon as it hatches, to dig into the 

 giant's belly in full security. 



How different are the conditions in the 

 Eumenes' cell! The caterpillars are im- 

 perfectly paralysed, perhaps because they 

 have received but a single stab; they toss 

 about when touched with a pin; they are 

 bound to wriggle when bitten by the larva. 

 If the egg is laid on one of them, this first 

 morsel will, I admit, be consumed without 

 danger, on condition that the point of at- 

 tack be wisely chosen; but there remain 

 others which are not deprived of every 

 means of defence. Let a movement take 

 place in the mass; and the egg, shifted from 

 the upper layer, will tumble into a trap of 

 legs and mandibles. The least thing Is 

 enough to jeopardize its existence; and this 

 least thing has every chance of being 

 brought about in the disordered heap of 

 caterpillars. The egg, a tiny cylinder, 

 transparent as crystal, is extremely delicate : 

 a touch withers it; the least pressure crushes 

 it. 



No, its place is not in the mass of pro- 

 visions, for the caterpillars, I repeat, are 



22 



