280 KANSAS UNIVERSITY SCIENCE BULLETIN. 



trip, usually — sometimes after every fourth — she would go 

 for water. This required twelve to fifteen seconds. She would 

 fly directly to the river below and alight on the agitated water. 

 Sometimes she remained on the water for as short a period 

 as six seconds. She continued to work in this way for an hour 

 and forty minutes, and then flew away. In twenty-five min- 

 utes she returned to work, and was still there when I left. 



At different times during the afternoon the wasp had mani- 

 fested marked uneasiness because of my presence. If I 

 crawled within eight or ten feet of the burrow she would in- 

 variably see me when she same out to drop a pellet, and then 

 she would not continue work until I had withdrawn several 

 feet. She never offered to fly away, as did the wasp previously 

 mentioned. She showed her uneasiness by keeping up a zig- 

 zag flight about the nesting site, usually between me and the 

 burrow. As soon as I would retire she would return to work. 



The next afernoon I found her digging again. I caught 

 her for identification and opened the nest. Opening the nest 

 was a tedious task. Careful digging was very slow. I had 

 expected to find a nest about three inches deep and with not 

 more than four cells. In spite of that hard clay, this nest 

 was seven and one-half inches deep and had twenty-two cells ! 

 What industry ! What a Herculean labor for a wasp ! And 

 her work had not been finished. 



The cells were arranged in five main galleries; some of 

 these had small branches. The galleries diverged obliquely 

 in different directions from the burrow, outlining a sort of a 

 cone in the talus. The first division of the burrow into gal- 

 leries was three inches below the entrance. The diameter of 

 the burrow was one-fourth inch. 



The cells were like ellipsoids. The diensions of an aver- 

 age cell were nine-sixteenths by seven-sixteenths of an inch. 

 The largest number of cells in a single gallery was six. The 

 walls of the cells and of the burrow were very smooth, almost 

 forming a layer of earth distinct from the surrounding talus. 



The nest had been in the course of construction so long that 

 a part of the brood had already emerged. Eight cells con- 

 tained only pupal exuviae. Nine cells contained pupse in 

 various stages of development, one of which emerged the next 

 day in a glass vial. Four cells contained grubs, three of which 

 were evidently mature. In one cell with the other grub were 



