50 Psyche [April 



Nest No. 2.^ Scarcely 24 hours had passed after the 

 tubes had been placed out, when a wasp was seen (June 13) 

 entering one of them carrying mud or gravel which she got at a 

 driveway 25 feet distant. Between each trip for gravel, which 

 always took several minutes, she took a shorter flight which I 

 could not follow, probably to her water supply. She continued 

 in this way from four until five o'clock P. M., when I was obliged 

 to leave. At six P. M. she entered her nest carrying beneath 

 her body a small green caterpillar, which she quickly deposited, 

 then flew away. Between six and seven o'clock she made about 

 six or seven visits to her nest, each time bearing a similar cater- 

 pillar. One of her absences from the nest was of only two or 

 three minutes duration, but usually she did not meet with such 

 prompt success. She spent no more time within the nest than 

 would allow her to deposit her prey. From this time on I ob- 

 served her only sufficiently to state that she worked quite con- 

 sistently for the next two days and completed her nest at some 

 time just previous to four P. M. on June 15. 



Nest No. 3. On June 16 at four P. M. a wasp of this species? 

 possibly the same one as described above, was seen to enter one 

 of the nesting places not far from nest No. 2, An examination of 

 the tube at this time showed two cells already completed. Out" 

 side the closing partition of the second cell was a third egg and a 

 single caterpillar. The wasp continued to work until seven P- 

 M. at which time she had nearly completed the closure of her 

 third cell. During the night she did not occupy the nest as these 

 wasps commonly do, possibly because there was hardly sufficient 

 room. Indeed, it seemed that she would not be able to construct 

 an additional cell in such a limited space. Observations at 5:30 

 and at 7:30 the next morning showed that the wasp had not re- 

 sumed her work, but by 8 :30 she had already finished the closing 

 partition of the third cell and had laid her fourth egg. During 

 the morning she caught and deposited three caterpillars and at 

 10:45 she brought the bit of cement that would have closed the 

 last cell had I not captured her for identification before she had 

 been able to apply it. 



3The numbers designating the nests described in this paper are the original ones used in my 

 field notes; they are thus not consecutive. 



