ISELY: EUMENID^ OF KANSAS. 285 



would run back and forth again, stopping occasionally in differ- 

 ent parts of the open space to repeat the sweeping. This 

 lasted for about five minutes, when, after concenti-ating her 

 sweeping on an area of about one square inch, clearing it of 

 loose earth and blades of grass, she took wing, made a circling, 

 zigzag flight over the scene of her activities, and flew away in 

 the direction of the river. 



I remembered that 0. papagorvm and 0. arvensis had be- 

 haved similarly before beginning work on a nest, so I sat down 

 on the grass as near the open space as I dared and awaited 

 developments. 



In forty seconds she returned, wet a spot in the little area 

 she had cleared, and began to dig with her mandibles and fore 

 feet, gathering the earth into a pellet, which she held in her 

 mandibles. After digging thirty seconds she arose and dropped 

 the pellet about eighteen inches from the hole. All the other 

 pellets she excavated were dropped about the same place. 

 Trips for water followed regularly after removing every five 

 or six pellets of earth. 



To ascertain how much time was spent in carrying water, 

 how much in extracting each pellet of earth, and how much 

 variation there was in the time spent on each part of the 

 work, I timed this wasp's trips. I kept the time record in 

 detail in my notes, showing the number of seconds used for 

 each trip for water and for removing each pellet of earth. I 

 shall here give the first part of this record from my notes. All 

 numbers, represent seconds. It follows : 



For water, 40; for removing pellet, 30, 15, 25, 20, 20. 



For water, 40; for removing pellet, 30, 25, 15, 25, 20, 20. 



For water, 30; for removing pellet, 15, 20, 20, 15, 30, 40. 



For water, 25; for removing pellet, 10, 30, 25, 35, 15. 



For water, 35; for removing pellet, 30, 30, 30, 15, 20, etc. 



Madam Dorsalis worked very steadily, never pausing while 

 in the vicinity of the burrow. She would take wing the in- 

 stant she backed out of the burrrow, and on dropping the pel- 

 let would fly directly back to it. 



She worked steadily from 10:35 A.M. until 11:15 A.M. 

 During those forty minutes she had removed eighty-six pellets 

 and made sixteen trips for water. Most of the time she had 

 been completely hidden while digging. When she returned 

 from her seventeenth trip for water she flew to the burrow 

 and started to enter, but when half way in she stopped sud- 



