1929 ] 
The Nesting Habits of Epinomia 
247 
with her heavy load of pollen was trying to effect an 
entrance to one of the holes. Whether she had been away 
from home during the storm and was just now returning, 
I do not know. The following night it rained again, and 
my next examination three days later, showed that they 
were making but slow progress in resuming activities; 
scarcely more than one-tenth of them had then been able 
to escape from their temporary imprisonment. From this it 
is at once apparent that rains are really a serious impedi- 
ment to the work of this species, even more than we see in 
the cases of some of the burrowing wasps, as Bembix mubi- 
lipennis and others, which scramble out uninjured almost 
as soon as the storm-clouds have blown away. May there be 
some correlation between this greater liability to injury in 
heavy rains and their habitual choice of high knolls for 
nesting sites? In three or four places on the ground were 
little masses of pollen which the females had lost in their 
extreme efforts to gain entrance to burrows closed by the 
rain. 
The next day the sun shone and there was a slight in- 
crease in activity, but in some portions of the field it 
appeared that there had been heavy mortality. On this occa- 
sion I made one more attempt at digging up nests. In follow- 
ing one, it was necessary to dig out a space about a foot 
across, and in so doing I broke into five other nests. I could 
follow only one of these channels, however ; it went straight 
down for 24 inches, and the worker was at the bottom. Three 
inches above the terminus was a lateral cell filled with 
golden pollen and containing a very young larva. 
In the area of the colony where the hill-top had recently 
been cut away, the nests occured in abundance on the top 
and some were very close to the edge of the sharp declivity, 
but there were none at all on the steeply sloping side. Since 
all of the burrows went straight down, some of the nests 
near the edge, although they were placed at a proper depth 
below the top, had very little protection of soil on the side. 
By September 12, the nests had almost regained their 
normal proportions, and one could hardly see that the rains 
had played havoc. The great majority of the bees had been 
able to dig out of their temporary prisons. When I visited 
