BEE-KILLING WASPS 115 



than a pinhe^d appeared, then this grew, as if by magic, until 

 the round face of the Philanthus was quietly and intently 

 gazing at us. Presently she slipped out through the opening ; 

 the loose earth lightly closed behind her and she flew away 

 on the morning air. 



P. punctatus seems to experience as little difficulty as 

 Bembix in finding her nest upon returning to it. She alights 

 from flight upon the very spot where her hole is concealed 

 under a little mound of loose dirt. Only once we saw one 

 in error; she entered a hole in the bank and came scuttling 

 out, then tried once more and emerged again. Then she 

 began digging at a spot right beside this hole and uncovered 

 her own nest only one-quarter inch away from the other 

 hole, the domicile of some other insect, which she had en- 

 tered by mistake. It is little wonder, however, that she com- 

 mitted the error, when her neighbor's door stood invitingly 

 open only one-fourth inch from where her own lay covered. 

 Repeated observations have taught us to expect to find the 

 mistress within the burrow if the door stands open, but 

 if during the day it is closed, she is probably away from 

 home. Since she makes chambers from time to time along- 

 side her tunnel, she probably alternates the work of excava- 

 ting and hunting. 



The bees, Halictus sparsus Robt. $ [ J. C. Crawford] , H. 

 versatus Robt. $ [J. C. Crawford], H. pruinosus Robt., 

 and various other species of Halictus, which we found in 

 the wasps' possession, in the burrows, or in the cells were 

 always dead. We saw no marks of violence on them to tell 

 us the manner of their death. Ashmead finds that these 

 wasps prey upon Halictus disparalis Cr. 



On one occasion we .tried to offer a bee with the thorax 

 crushed to a Philanthus which was finishing her burrow. 

 Repeatedly we laid it at the mouth of the burrow, but just as 

 often she carried it back and discarded it. A second Philan- 



