BEHAVIOR OF POMPILID WASPS 51 



hour, only occasionally kicking or sweeping a little dirt off 

 the spider. We suspected that she did this, not for the 

 sake of keeping her spider cleared, but merely to follow her 

 habit of occasionally clearing away the debris around her 

 doorway. Some tiny ants hung around a bit inquisitively; 

 the wasp came out of the hole and bit at them, kicked at 

 them and curled up her sting at them menacingly until they 

 withdrew. 



Once when the wasp had swept the dirt off the spider 

 it stirred, scrambled to its feet and walked away three 

 inches, whereupon she promptly pounced upon it and the 

 pair rolled over in a tumble she probably stung it then 

 as it lay quiet she calmly mounted its back and precisely 

 curled her abdomen around its body and planted a deliberate 

 sting in the ventral part of the thorax, just in front of the 

 last pair of legs; then she took it back and laid it up-side- 

 down with care, at the mouth of the hole and resumed her 

 digging and kicking dust all over it. So, to try her, when 

 she was deep in the hole we drew the spider back two inches 

 and turned it right-side-up. When the wasp emerged she 

 saw it but paid no attention to the fact that its position had 

 been altered. On her second appearance it began to wiggle 

 its legs; she pounced upon it ferociously and tumbled over, 

 probably stinging it, as the spider did not resist further; 

 then she casually stung it again, as if for good measure, 

 between the third and fourth pairs of legs; then as it lay 

 on its back she most deliberately placed her sting between 

 the second and third right legs, near the center of the body, 

 and left it there for several seconds, while the spider con- 

 vulsively drew up its quivering legs and stirred no more. 

 Tiny drops of juice oozed out of the wounds; she paused 

 and seemed to drink this. Then she marched away with a 

 most triumphant and self -satisfied air. 



By this time she had apparently learned that she could 



