THE WOOD-BORERS 



the nest when the female brings a spider, the nest being 

 enough larger than in rubrocinctum to accommodate 

 them both comfortably. As a usual thing, however, he 

 enters on the back of the female. The spiders brought 

 by albopilosum are larger than those used by rubrocinc- 

 tum. They sometimes bring such heavy specimens of 

 Epeira insularis that they are carried with difficulty, 

 the wasp alighting and dragging the spider into the 

 hole instead of flying directly in as usual. 



We watched a number of albopilosum nests during 

 the second summer, finding them in several instances 

 through the loud humming of the female while she was 

 pushing the spiders into her hole. From our not very 

 extensive study of the spiders taken by this species we 

 are of the opinion that some are killed at the moment 

 of capture, while others that are only paralyzed die in 

 the nest from day to day. 



Mr. W. H. Ashmead has noted that albopilosum 

 stores its nest with aphides, but in the cases that we 

 observed they used only spiders. There can be no mis- 

 take on this point, as we more than once took the spider 

 from the wasp as she was entering the nest. In a recent 

 letter Mr. Ashmead says that his notes were made in the 

 field, and that he probably mistook some closely allied 

 species for this one. 



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