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Psyche 
[Vol. 92 
fashion” (Fig. 1; Olberg, 1959). (2) She bites at the soil around the 
nest entrance, and scrapes the loosened material into her nest. These 
are the same scraping and biting movements that are used during 
digging, only the body is now oriented away from the nest rather 
than toward it. (3) The wasp may also nudge or push soil ahead of 
her into the burrow with the front of her head (Fig. 2; Tsuneki, 
1963; Cazier and Mortenson, 1965). (4) Some wasps pick up clods of 
soil, clumps of sand or stones in the mandibles and drop or place 
them in the nest (Carpenter, 1930; Adriaanse, 1943), often pressing 
them into the substrate (Fig. 3). In most species the wasp fills her 
nest with soil from the mound that accumulated at the nest entrance 
during digging ( Sphex , Prionyx, Palmodes, Podalonia; Parker, 
1915). However, in Ammophila where there is no mound, much of 
the burrow is filled with stones and debris found around the nest 
which are picked up and placed in the burrow. Soil is also chewed 
from the surrounding substrate and scraped in. Biting and scraping 
at the soil around the nest also occurs in Sphex when the mound is 
insufficient to completely fill the main tunnel. This is particularly 
common in S. pensylvanicus which digs exceptionally long, multi- 
chambered nests which it occupies for many days. When females of 
this species finally come to filling the main tunnel, the mound has 
often disappeared. She chews soil from around the nest entrance, 
often breaking down the sides of the tunnel and leaving a wide 
depression where the entrance once was. When there is more than 
one brood chamber in a nest (Sphecini), soil from digging the next 
side tunnel may be used to close off the previous one. (Ammophilini 
have only one brood cell in a nest.) A few species (A. placida, A. 
zanthoptera and A. pubescens) have been observed to dig “false 
burrows” or “mines” during nest closure, using the dug material to 
fill their nest (Adriaanse, 1943; Evans, 1959, 1966c). Adriaanse (1943) 
suggested that in A. pubescens the building of a mine was associated 
with a lack of suitable material for closing at the surface. I have 
observed similar behavior in Sphex ichneumoneus when they do not 
have enough soil on the mound with which to close the nest. This 
can occur after a rain or when another female has filled her nest with 
soil from her neightbor’s mound (similar behavior has been de- 
scribed for other Sphex by Iwata, 1976). 
Wasps complete the burrow filling by either continuing to add 
and pack soil, by piling up stones, by packing stones into a kind of 
