4 Trans. Acad, of St. Louis 



ulating the head and thorax in a lever like fashion. With 

 this exertion they make a great deal of stridulating noise, 

 similar to the sharp squeak which they emit when they 

 are held up squirming in the forceps. These Mutillids in 

 the jelly-glasses seldom came to the top. After four days 

 had elasped an examination was made; both wasps and 

 larvae seemed healthy, but there was no evidence of any 

 parasitism. The beetle larvae were fed on insects, but 

 nothing was placed in the cages for the Mutillids, yet at 

 this time they looked none the worse for lack of food. 

 Since propinquity did not affect them, the experiments 

 were abandoned. 



A dozen or so other Mutillids were kept for later study 

 in a fish-globe. There was no soil in this glass jar, but 

 a few grape-leaves were strewen on the bottom for the 

 comfort of the insects, and in one corner was a cloth kept 

 moist with sweetened water. During the first two days 

 they were out and active, and at night they would creep 

 in between the folds of the leaves for sleep, but later 

 when they were in a weakened condition they seldom 

 came from their hiding places. They lived only a week ; 

 just why they were so short-lived I do not understand, 

 since without food the others lived nearly as long. It 

 may be that they were more comfortable in the damp cool 

 earth of the jelly-glasses, or perhaps they found some- 

 thing of a nutritive nature in the soil. I have spoken 

 only of the females so far, because in several visits to this 

 area in early July, no males had been discovered. 



Some twelve days later, July 24-25, a thorough search 

 was made in this same area and then only males were 

 abundant and only the species Bruesia bexar Blake [S. 

 A. Rohwer]. They were constantly on the wing in a zig- 

 zag flight from two to four inches above the ground. 

 Their stops were few and far between, and they paused 

 only for toilet-making. I suppose they were seeking 

 the females. The priority of the emergence of one 

 sex seems here to be reversed, at least in so far as 



