WOOD-BORING WASPS 137 



semi-gregarious way, in a wood-lot. While they were fairly 

 numerous about the half-dozen long rows of cord-wood, 

 there was only one spot at the end of one row where from 

 five to eight individuals congregated at a time for play. They 

 would fly about the top of the pile of wood at a height of 

 five feet, chasing one another on the wing for an hour or so 

 at a time, doing nothing in particular but to play thus in the 

 sun. Both sexes were present, so we thought it might pos- 

 sibly be a coquettish behavior preparatory to mating. A 

 certain scar on one of the logs, where a branch had been 

 cut off, was the one and only place where they would rest. 

 One at a time they would select this spot, ignoring all the 

 similar ones at hand, and remain there quietly until dis- 

 covered and put to rout by the others. The latter would 

 chase her (it was usually the females who sat down to rest) 

 back into the crowd. During the afternoon we saw five 

 groups there, in turns, frolicking in the sun ; but the beha- 

 vior never varied, the location never changed, and the cut 

 end of this one log never seemed to grow less attractive. 

 Yet during all this performance we saw no attempt at 

 mating. 



Trypoxylon johnsoni Fox. [S. A. Rohwer] . 



For our knowledge of this species, we must depend largely 

 upon mere surmise or regular detective methods. We have 

 seen it active only once, when, at Lake View, Kansas, on 

 July 27, it entered three holes in a clay embankment. What 

 its errand there was we did not ascertain, whether searching 

 for a domicile or hunting prey. 



A year later we got our next clue to her ways of living. 

 A stem of some soft wood was found, near to the ground % 

 inch in diameter and 13 inches long. It had been hollowed 



