THE BUG-HUNTERS. 95 



o'clock in the morning the work is carried on without haste and 

 with frequent pauses until two or three in the afternoon, when 

 it is suspended. Bicolor goes in for the night at about four 

 o'clock and nothing more is seen of her until the next morn- 

 ing when about an hour's labor completes the nest. 



She invariably leaves the nest open when she goes away, but 

 in every case that came under our notice the spot chosen was 

 protected by the branches or leaves of some weed so as to be 

 invisible from above. She is rarely fortunate in one respect, 

 since we have never seen a parasitic fly in attendance upon her; 

 but this fact makes it difficult to explain her wily and cautious 

 approach to the nest. "Why should she spend so much time in 

 getting in, scarcely ever dropping directly down to it as other 

 wasps do? On entering she often leaves the hole open and just 

 as often closes it. The closure at night is doubtless to protect 

 the nest from cold and dampness but in day-time it may be 

 merely the result of her pushing back the loose earth which 

 bars the passage to the nest. There is no attempt to clear away 

 the earth from the outside. The appearance of the nest is al- 

 most identical with that of an ant-hole, a tiny opening with a 

 circular heap of earth around it. The entrance tunnel is from 

 two and one-half to three and one-half inches in length and the 

 nest itself is from one and one-half to two and one-half inches 

 below the surface. 



In one of the nests that we opened we found three bugs. 

 These we put into a glass with the wasp that had taken them 

 in. She took each one in turn, and, standing over it', venter to 

 venter, squeezed its neck very slowly for half a minute or more. 

 We offered her several live specimens of the same species but 

 she would not touch them. Of those that were taken from the 

 nest, one was injured in being taken out, one was nearly dead 

 and the third was very lively. The second one lived three and 

 the third one five days after wet disinterred them. 



At another time, having found a wasp that was provisioning 

 her nest, we waited until she went in with her load and then 

 placed over the opening an inverted tumbler containing seven 



