ANIMAL BEHAVIOR, WITH EXAMPLES 



195 



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The Golden Sphex as the 

 Grasshopper's Enemy 



N our casual observations of the life of insects, 

 how seldom their real enemies are given due 

 consideration. I have in mind at this moment 

 the part played by the wasps in limiting the 

 number of grasshoppers. I have witnessed the destruction 

 of the eggs of the green meadow grasshopper, Orchelimum, by 

 a parasitic species Macroteleira, but I am now about to relate 

 my observations on the large golden digger wasp, Sphex ichneu- 

 Tnonea. She stores her underground nest with grasshoppers 

 which she captures by paralyzing them with a sting from her 

 ovipositor. 



On September eleventh I came upon a freshly made burrow 

 of the golden Sphex wasp, situated only a few yards from 

 the back door of our cottage. Thereafter I kept constant 

 watch with the expectation of discovering the owner of the 

 burrow. Three days later a little pile of dirt close to the 

 entrance indicated that fresh excavation had been in progress 

 which caused me to renew my vigilance. On the fourteenth, 

 near the noon hour, I was surprised by the appearance of the 

 owner, a large orange-colored Sphex wasp. She had made her 

 way along the ground unobserved and at first halted about three 

 inches from the opening of the burrow. She was in this position 

 when I first caught sight of her. At the same time she dropped 

 a robust, green, meadow grasshopper, which she had been drag- 

 ging along the ground. After discharging her burden she 



