128 THE SOLITARY WASP. 



taken out we sifted it through our hands in vain. At last we 

 acknowledged ourselves beaten, and trudged home empty- 

 handed. 



Our pride was destined to be still further humbled. Three 

 times within that same week we saw the Tornado Wasp bury 

 her spider, and three times we failed, just as incredibly, to find 

 it. On the last of these occasions we did not let her fill the nest, 

 attempting to follow the tunnel and get out the spider as soon 

 as the egg was laid, but the lose unstable character of the soil 

 defeated us. 



Our fifth example, however, dug her nest, not among the 

 beans but lower down in the potato field, where the ground was 

 firmer, and here we made our first successful excavation, suc- 

 cessful only up to a certain point, since in getting out the spider 

 we dislodged the egg, and although it was at once replaced it 

 never developed. The spider was placed three inches below 

 the surface but we could not trace Jie tunnel. At our next 

 opportunity, wishing to make good this failure, we placed a 

 blade of grass in the opening just after the wasp began to fill it. 

 On being disturbed she assumed the most comically threatening 

 aspect, whirling around, lifting her wings, and then circling 

 about us. As soon as we moved back she dashed at the grass- 

 blade and pulled it out with great energy. A few minutes later 

 we made a similar attempt and again she frustrated our plan, 

 but when we inserted the grass-blade for the third time, the 

 nest being now half filled, she let it remain. Some hours later, 

 with this to guide us, we succeeded in tracing the nest, but 

 much to our disappointment found it transformed into a ban- 

 queting hall. Scores of tiny red ants had discovered this rich 

 store of food. They had eaten the egg and were rapidly finish- 

 ing the spider. 



Twice afterward, in opening these nests, we found the same 

 ants in possession before us. It is probable that they are a 

 formidable enemy to this and other species of Pompilus, but 

 they seem to find the spider by burrowing beneath the surface, 



