WASPS THAT PREY ON BEETLES 129 



The six beetles taken from our nest were watched over 

 carefully, but no signs of life were visible, with all the usual 

 methods of stimulation. The conclusion was that C. fumi- 

 pennis kills her prey outright, although it might be possible 

 that these beetles feign death when stimulated. 



The Peckhams, according to Wheeler, 2 find that other 

 species, like the majority of European Cerceris, prey upon 

 weevils, but that C. fumipennis preys upon a Buprestid 

 beetle, Chrysobothris 4-impressa "which it kills outright," 

 while Ashmead, 3 citing Hubbard, says they provision their 

 cells with Chrysobothris deutipes, and Grossbeck 4 finds that 

 they use three species of Buprestids for prey : Dicerca punc- 

 tulata, Buprestis lineata and Chrysobothris floricola. He 

 also says that their mounds resemble conical ant hills which 

 are about two and one-half inches in diameter, the depth 

 four and one-half to six inches, and there is no widened cell 

 at the terminus. His statement, however, that at the bottom 

 of some burrows paralyzed Buprestids were found shows 

 that it is still an unsettled problem whether C. fumipennis 

 paralyzes her prey or kills it outright. 



Scolia dubia Say. [S. A. Rohwer]. 



While we had been examining Howard's Hill 5 several times 

 a week all summer, we had neglected to penetrate one small 

 corner near the stables. Here we discovered Scolia dubia on 

 September 15, 1915. Whether these wasps had come here 

 late in the season, or whether they had been there for some 

 weeks is not known, but this much is certain : if they had 



2 Journ. Animal Behavior 3 : 383. 1913. 



3 Psyche 7 : 60. 1896. 



4 Journ. N. Y. Ent. Soc. 20: 135. 1912. 



5 A large tract of land situated in the southwestern part of St. Louis. 



