WASPS, SOCIAL AND SOLITARY 



Moreover, when their prey was laid down for a moment 

 on the way home, they felt the necessity of noting the 

 place carefully before leaving it. 



Of the species that catch their prey before making 

 the nest we have good examples in Pompilus quinqueno- 

 tatus, the tornado wasp, and fuscipennis, the Pompilus 

 with the red girdle. 



The tornado wasp may make her nest anywhere from 

 one to ten feet from the spot on which she has deposited 

 her spider, while fuscipennis never goes more than four- 

 teen inches away. During the process of excavation 

 both of these wasps pay several visits to the spider, and 

 frequently they have difficulty in finding it. As an ex- 

 ample of this kind of trouble we give a diagram of the 

 course followed by an individual of fuscipennis after 

 she had finished her nest, in trying to -find her spider 

 and in bringing it home. This and the other similar 

 diagrams that are given are reductions of large tracings 

 that were made on the spot. Although not absolutely 

 correct they are exact enough for all practical purposes, 

 since wherever there is an error it is necessarily in the 

 direction of making the path pursued by the wasp 

 appear shorter and less complex than it really was. 

 The individual in question had placed her spider on a 

 cucumber vine which lay on the ground, not hidden by 

 282 



