The Fly-hunt 



burrow with her capture held under her ab- 

 domen between her legs. Here comes one, 

 the Tarsal Bembex {B. tarsatci), who ar- 

 rives laden with a Bee-fly. The nest is sit- 

 uated at the sandy foot of a steep bank. The 

 huntress announces her approach by a shrill 

 humming, which has something plaintive 

 about it and which continues until the insect 

 sets foot to earth. We see the Bembex hover 

 above the bank and then dip straight down, 

 very slowly and cautiously, all the time emit- 

 ting her shrill hum. Should her keen eye 

 descry anything unusual, she slackens her 

 descent, hovers for a second or two, goes up 

 again, comes down again and flies away, swift 

 as an arrow. After a few moments, here 

 she is once more. Hovering at a certain 

 height, she appears to be inspecting the lo- 

 cality, as if from the top of an observatory. 

 The vertical descent is resumed with the most 

 cautious slowness; finally, the Wasp alights 

 with no hesitation w^iatever at a spot which 

 to my eye has naught to distinguish it from 

 the rest of the sandy surface. At that in- 

 stant, the plaintive whimper ceases. 



The insect, no doubt, has landed more oi 

 less on chance, since the most practised eye 

 cannot distinguish one spot from the other 

 305 



