isely: eumenid^ of Kansas. 279 



minutes in the nest, and in fifty-seven minutes she brought 

 another caterpillar. Like others of this genus, she carried it 

 head foremost, ventral side up, grasping it with her man- 

 dibles and one pair of legs. She entered the tube dragging 

 the caterpillar under her body. 



The next afternoon I found her digging again. I took her 

 for identification and opened the nest. The height of the tube 

 was a little over one-half inch and its diameter was one-fourth 

 inch. The tube was but slightly bent. Its walls were three- 

 sixteenths of an inch thick, and their exterior surface was 

 coarsely granular, like that of 0. arvensis. 



The burrow was nearly perpendicular. Including the cells, 

 its depth was three inches. There were three cells, two in one 

 gallery, which were stored and sealed up, and a single cell 

 which was being excavated at the time I took the wasp. The 

 cells were nearly globular and were one-half inch in diameter. 

 Those that were stored were closed with thin mud caps. The 

 walls of the burrow and the cells were packed, but did not 

 form a layer of earth distinct from that surrounding them. 



The two closed cells were stored with caterpillars, four and 

 six respectively. Neither cell was packed. The caterpillar 

 used was a naked green noctuid with three rows of dots on 

 its sides. It averaged 15 mm. in length. I did not find the 

 egg. 



The third wasp of this species whose nesting activities I 

 observed worked in the hard clay talus on a cliff, by the Saline 

 river. She was an unusually large wasp for this species. The 

 nest was first found by Mr. Williams, July 24. He marked 

 the place and showed it to me that afternoon. 



The burrow opened under a small flat stone — rather a flat 

 pebble — which formed a protective ledge. From the entrance 

 of the burrow, under the stone, the wasp built a horizontal 

 tube similar in texture to the tube of the nest previously de- 

 scribed. It was about one-third of an inch long. The clay 

 in which the nest was excavated was very hard, so that I 

 could scarcely dig in it with my digging knife. 



The wasp was carrying out pellets when I first saw her. 

 She would back out of the burrow, fly four or five feet and 

 drop the pellet, and then return directly to work. Each ex- 

 cavation of a pellet required from two minutes and ten sec- 

 onds to two minutes and thirty seconds. After every third 



