isely: eumenid^ of Kansas. 261 



The next three successive trips for water were made at in- 

 tervals of approximately four minutes each. 



After fifteen minutes' work the wasp was completely hidden 

 in the tube when digging. After fifty minutes the tube was 

 one and one-fourth inches long, and near the tip it was curved 

 downward. She then began discarding the excavated pellets, 

 no longer using them to add to the tube. She would back out 

 of the tube with the pellet in her mandibles, poise on wing a 

 moment, just long enough to drop the pellet, then she would re- 

 enter at once. When she began dropping the pellets I supposed 

 that the tube-building was finished. However, when I re- 

 turned, within only two hours after the excavations had been 

 started, the tube was two inches long. At this time it was 

 finished, I believe. 



I left her then, still dropping pellets. She had begun dig- 

 ging at 2 :30 P. M. July 5. The next morning when I took my 

 place before the clifl" she was provisioning her nest with cater- 

 pillars. But the nest-building had not been completed, for in 

 the afternoon of July 6 she was again excavating, probably 

 adding more rooms to her house. 



I have observed many of these wasps at work on their nests ; 

 a few of them I noted when the excavation began ; and the rou- 

 tine of work — the method of digging, the building of the tube, 

 the dropping of pellets, and the occasional trip for water — was 

 essentially the same. 



There was little regularity about when time should be spent 

 on tube-building. The tube was always started at the be- 

 ginning of the work. Often it was finished before any of the 

 pellets of earth excavated from the burrow were thrown away. 

 On the other hand, I have noted a number of instances in which 

 the tube was scarcely more than started when building it 

 further seemed to be abandoned ; the excavated earth was dis- 

 carded. After one or two cells had been dug and provisioned, 

 work on the tube would again begin. 



Earth used in tube-building, as I have stated previously, is 

 usually excavated from the burrow. There are rare instances, 

 however, in which this is not the case. I noted one wasp dis- 

 card most of the earth taken from her burrow one afternoon. 

 The next afternoon she laboriously collected particles of earth 

 from the side of the bank several feet below her nest with 

 which to lengthen her tube. I noted another wasp set about 

 lengthening her tube after she had wasted much soft earth 



