The Yellow-winged Sphex 



she seizes them and the game is brought 

 quickly down to the lair. 



I still ask myself, without being able to 

 find a sufficiently convincing solution, the 

 reason for these complicated proceedings at 

 the moment when the Cricket is introduced 

 into the burrow. Instead of going down to 

 her den alone, to reappear afterwards and 

 pick up the prey left for a time on the thresh- 

 old, would not the Sphex have done better 

 to continue to drag the Cricket along the gal- 

 lery as she does in the open air, seeing that 

 the width of the tunnel permits it, or else to 

 go in first, backwards, and pull him after 

 her? The various Predatory Wasps whom 

 I have hitherto been able to observe carry 

 down to their cells straight away, without 

 preliminaries, the game which they hold 

 clasped beneath their bellies with the aid 

 of their mandibles and their middle-legs. 

 Leon Dufour's Cerceris begins by complicat- 

 ing her procedure, because, after laying her 

 Buprestis for a moment at the door of her 

 underground home, she at once enters her 

 gallery backwards and then seizes the vic- 

 tim with her mandibles and drags it to the 

 bottom of the burrow. But it is a far cry 

 71 



