196 Trans. Acad. Sct. of St. Louis 
Ant-lion larvae. Myrmeleon mobilis. & M. 
ammaculatus. 
House spider. Theridion tepidariorum. 
(c) Renters. 
In this chapter are enumerated the secondary inhab- 
itants of the old clay bank, those which came as ten- 
ants of the burrows made by some of the creatures 
listed in the foregoing chapter. These, for the most 
part, were less hardy than the pioneers; they came into 
the community, evidently quite willing to utilize its ad- 
vantages and share its comforts, Often they dropped 
in merely for shelter or food, and remained to the end 
of their days. These renters, besides using the old dwell- 
ings, influenced the population of the unit in two ways 
—by using the other inhabitants for food, and often by 
being eaten by them. 
The Pompilid wasp, Pseudagenia mellipes Say. 
This wasp was occasionally seen about the clay bank. 
There were four in 1917 and perhaps a dozen in 1920. 
In ‘‘ Wasp Studies Afield’’ we have told how this crea- 
ture nests in both new and secondhand domiciles; some- 
times she makes small mud nests under loose bark (one 
such nest was found inside an oak-apple lying on the 
ground), and at other times she modifies the nests of 
the mud-daubers to suit her needs. 
The interest of P. mellipes in the bank was the prey 
which it sought there. The wasps were often seen going 
into the old bee-burrows, now occupied by spiders, prob- 
ably in search of food for their young. On a few occa- 
sions, they were seen going elsewhere for prey and 
