424 Trans. Acad, Sci. of St. Louis 
about the place until July 7. Since the Peckhams had 
already described these wasps as nesting in old holes in 
a post, as soon as I saw them going from hole to hole I 
at once suspected that they were foraging for spiders in 
the old bee burrows and carrying their booty away to 
their nests elsewhere. After some days, however, it be- 
came evident that they were actually nesting in the aban- 
doned bee-burrows. Then I realized that I had erred in 
thinking that they had come from elsewhere to forage 
here; they had in all probability emerged from nests 
near by and similar to those which they were making. By 
July 30th, several females were at work clearing out the 
old burrows for nests and bringing provisions. 
While the heavy work of nest-making and hunting falls 
to the female, yet the male renders some service in 
spending his time at home and probably warding off in- 
truders. As the Peckhams’ have so prettily described, 
the male keeps watch at the doorway of the burrow; 
when the female returns to the nest with a spider, he flies 
out to make way for her, and then as she goes in alights 
on her back and enters with her. I have further observed 
that this trick is more than a bit of indolence or pretty 
play; I have on several occasions clearly seen that mat- 
ing actually oceurs during this short period—not always, 
but frequently. Nor is the male always the sole ag- 
gressor in this unique bit of flirtation. In one nest in 
particular which I watched while the mother went 
a-hunting the male deserted his post in the mouth of the 
burrow and wandered about on the outside a few inches 
from the hole. The returning female, not being greeted 
by the physiognomy of her spouse as she neared her 
doorway, hovered about the aperture for a few seconds 
until she spied him, whereupon she stopped short and 
7 Psyche 7: 303-306. 1895. 
