188 Psvche [December 



opening was left above the door, with the hope that the wasps 

 would learn to go afield and capture their own prey. 



At half past five in the afternoon, when I left the insectary for 

 the day, all of the wasps were resting quietly or else cleaning their 

 antennae. At a quarter to six next morning, when I returned to 

 the insectary, I discovered that the wasps had eaten out all of 

 the contents of the thorax of the pupa and had thrown the body 

 to the shelf below. The contents of the abdomen had not been 

 touched. 



From this date to the twenty-eighth of August the wasps were 

 daily fed on caterpillars of the cabbage butterfly or on other 

 lepidopterous larvte. Certain wasps would accept the larvae and, 

 after malaxating them in the manner described above, feed 

 the wasp larvse and even the adults. Other wasps would not 

 take the caterpillars. It may be that these latter wasps acted as 

 guardians of the nest. If so they were not very efficient. The 

 rearing on the hind legs, the darting forward and backward, the 

 waving of the antennae and the moving of the wings, although 

 they may be defensi^'e movements, certainly are not formidable. 

 I placed some caterpillar larva? on the top of the nest. The wasp 

 that had been functioning as nurse captured one of them; but the 

 other wasps on the nest made no attempt to either bite or sting 

 them. Indeed, the only stingmg done during the time these 

 wasps were under observation was when I was attempting to 

 induce them to feed upon the larvse of the squash bug {Anasa 

 tristis). Grasping a bug in a pair of small forceps, I offered it to 

 a wasp. She darted at the bug and, with her mandibles, dashed 

 it to the shelf below. I presented it to her four times in succes- 

 sion. Each time she behaved as above. The fifth time the 

 squash bug was presented, the wasp darted at the forceps and 

 struck out with her sting, which slipped along the forceps and 

 stuck in my finger. The wasp fell to the shelf below and then 

 returned to the nest. A few minutes later I offered her a cabbage 

 butterfly caterpillar, to which she responded in the usual manner. 

 Although regularly supplied with caterpillars, yet these wasps 

 would occasionally feed their young upon honey collected from 

 a watch glass. 



At five minutes to five on the afternoon of August the twenty- 

 eighth a wasp found the crack above the door and passed through 



