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Tolerance. It is of interest that in several cases more 

 than one female was fonnd in the lield associated with a single 

 host larva. In experimental work along this line there seemed 

 to be no limit whatever to the number of Scleiodermus i>n- 

 migrans Avhich would simultaneously but without any particu- 

 lar cooperation join in mastering a single beetle grub and the 

 relatively enormous full-grown grubs of Xystrocera glohosa 

 (Olivier) and Aegosonm reflexwn Karsch were always ulti- 

 mately overcome if enough individuals were placed with them. 

 Further, these females invariably lived in harmony upon the 

 paralyzed prey, oviposited, and the progeny of the diiferent 

 females fed and reached maturity without interference from 

 the others. This tolerance extended even to the grubs of other 

 species of Sclerodeimus and, while the experimental work was 

 not continued as long as is desirable, adults of different 

 species were secured which had developed together on the 

 same larva. This interspecific tolerance is the more surpris- 

 ing from the fact that Sclerodermus inimigrans readily at- 

 tacked and fed upon and its grubs developed to adults on the 

 grubs of bees of the genus Nesoprosopis; of the fossorial wasps 

 Crabo and SceViphron; the ants, Tetramorlum guineense (Fab- 

 ricius) and Camponotus macidatus (Fabricius), and even the 

 ]>raconid and Chalcidoid parasites, Hormiopterus and Eiipel- 

 iniis which were associated with the Neoclytarhis. 



Conflicts of Sclerodernuis irmiiujrans with its Prey. A fe- 

 male was observed attempting to sting the prepupal larva of 

 Neoclytarlus euphorbiae. She grasped the edges of the sutures 

 of the middle of the abdomen with her mandibles and holding 

 on with her legs, curved her abdomen and body around the larva 

 attempted to sting it on the ventral side in the vicinity of the 

 suture between the fifth and sixth segments. The larva res]»ond- 

 ed to this efl^ort by violent contortions during which it rotated 

 first in one direction and then in the other, but without Ijeing 

 able to dislodge the Sclerodermus. I could not make out 

 whether she was able to penetrate its skin with her sting. 



A female placed with a larva of Neoclytarlus was ob- 



