200 
Psyche 
[Vol. 90 
fairly rigid with the exception of the abdominal pumping motion 
and a slight rocking of the body. The head was cocked downward 
somewhat and the antennae wiggled slightly. The whole process 
lasted about 60 seconds. 
Immediately after oviposition the female left the nest and 
returned with leaf material. Most often this was a large oval-shaped 
piece that was sealed to the leaf pulp ring. An occasional female 
returned with Oenothera strips and added to the ring but most often 
the entrance to the cell was immediately closed by adding the oval- 
shaped pieces. Once the cell was closed, the apical partition was 
constructed in the same manner as the basal partition. 
In almost all nests at least 1 partition, not associated with a 
provisioned cell, was constructed in the front of the nest to form a 
vestibular and an intercalary cell. This partition was constructed in 
the same manner as partitions defining provisioned cells, i.e., soil, 
leaf pulp, and whole leaf pieces were incorporated. The nest plug 
made to close the entrance was also constructed of the same mate- 
rial as partitions but was considerably thicker. The behaviors 
involved in plug construction were identical to those involved in 
partition formation. In addition to size, the closing plug differed 
from partitions in that it was often a series of partitions interspersed 
with soil and leaf pulp placed one atop the other. The outside sur- 
face of the plug was also different in that it contained much more 
soil than partition surfaces. Often what appeared to be pure soil was 
found on the outside surface of the plug, although leaf pulp was still 
used as the binding matrix. 
Usually E. pugnata built 1 cell a day, but occasionally some 
females began provisioning a second cell. In the greenhouse E. pug- 
nata provisioned cells in the morning when pollen was available and 
built partitions and plugs in the afternoon and early evening hours. 
Cell provisioning took 3.5 hours on the average. The number of 
pollen-nectar trips per cell varied from 36-44. Nectar and pollen 
deposition took roughly the same amount of time; nectar deposition 
= 38.7 sec. (standard deviation, sd = 12.3), pollen deposition = 32.4 
sec. (sd = 6.6). Foraging trips ranged from 2 min. 28 sec. to 9 min. 22 
sec. and averaged 4 min. 59 sec. (sd = 1 min. 38 sec.). Plug and 
partition construction took approximately the same amount of time 
as provisioning so that a nest with 1 cell, 1 intercalary partition and 
