298 KANSAS UNIVERSITY SCIENCE BULLETIN. 



and reentered the burrow head first. Twice more she tried 

 to enter the burrow and failed. Then in evident disgust she 

 flew away. 



In eight minutes she returned, entered the burrow, came 

 out quickly, and again tried backing into it. Her third at- 

 tempt was successful. This time both of her wings caught 

 outside of the rim of the burrow, but by several minutes of 

 pulling and twisting she bent them so that she could enter. 



She stayed in the burrow four minutes, and then at once 

 began storing more caterpillars. After her sixth trip I caught 

 her for identification. 



This wasp was the fastest worker of all the members of this 

 genus that I had observed. The time she spent inside the bur- 

 row storing her caterpillar varied from five to eight seconds. 

 She entered the burrow quickly and did not waste a moment, 

 starting on the hunt as soon as she had backed out. Also she 

 was the quickest to return to her nest with prey. Seven of 

 the hunting trips which she made before trying to oviposit I 

 timed as follows : 7, 6, 3, 4, 4, 6, and 7 minutes, respectively. 

 After oviposition the time of the trips was as follows: 5, IVi, 

 3, 4, 8, and 7, respectively. This wasp could go to the field, 

 bring in a caterpillar and store it in the average time re- 

 quired by 0. papagorum for the storing process alone. 



After taking the wasp I opened the nest. It contained four 

 cells, three in one gallery, and one cell directly behind this 

 gallery. As the burrow entered the cliff it pointed in hori- 

 zontally and then curved downward. The cells were prac- 

 tically vertical, and were arranged one above the other. 



The base of the lowest cell was about three inches below the 

 entrance of the burrow. The burrow at the entrance was 

 nearly one-fourth of an inch in diameter. The cells were ten- 

 sixteenths of an inch long and six-sixteenths of an inch in 

 their widest diameter. 



These cells were built in the cliff; they were not simply ex- 

 cavated, but were distinct from the earth that surrounded 

 them, so that when it was removed I was able to take out the 

 cells and remove them to a box. When removed, these so 

 closely resembled the much larger cells of Anthrophova occi- 

 dentalis that I was led to bel'eve that the wasp did not build 

 this nest, but preempted a nest of one of the smaller digger 



