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Psyche 
[June 
were not hidden from view, were made of silk, often approximately 
tubular, and usually open at both ends. The dark-colored spiders 
contrasted with the white woodwork as they rested in these retreats, 
and were thus easy to locate visually. Spiders in the field were 
usually impossible to see because their retreats were generally in 
curled leaves or under flakes of bark. 
When sufficiently disturbed during the day, the spiders dropped 
out of their retreats. Sometimes they stopped before they reached 
the ground, hung motionless at the end of their trail lines for a 
short while, then climbed back to their retreats; other times they 
descended to the ground. Although they often began to crawl as 
soon as they landed on a flat surface, they usually remained motion- 
less with their legs pulled tight against their bodies when they landed 
on irregular surfaces such as grass or leaf litter. 
Predatory behavior of A genoideus humilis 
A genoideus humilis is relatively rare in the northeastern U.S. 
(Evans and Yoshimoto 1962) but was not hard to find around the 
cottage on Lincoln Pond, and has previously been collected there by 
both Kenneth Cooper in 1952 and Robert Matthews in 1967 (un- 
published reports to the Trustees of the E. N. Huyck Preserve, Inc.). 
Evans and Yoshimoto summarize the literature on the biology of 
this species, noting that it is often found near buildings. It has been 
recorded preying on orb weavers in the araneid genera Neoscona , 
Araneus , and Conepeira , but there are no records of its predatory 
behavior. 
Females of A. humilis were observed hunting for spiders on the 
walls and windows of the cottage. Typically, a wasp walked along 
the surface of the wall until she encountered a crack between two 
shingles, then walked up the crack and under the overlapping shingle, 
often staying out of sight for 30 seconds or more. The wasps did 
not investigate every crack they encountered, and often passed two 
or three before walking up one. They usually showed no obvious 
reaction when they encountered silk in them. Occasionally a wasp 
bent her abdomen forward beneath her so that the tip was near 
her head as she entered a crack. 
Four complete wasp-spider encounters were observed. One in- 
volved a spider resting in a horizontal retreat at the top edge of a 
window pane. The wasp, after passing within two cm of another 
spider in a retreat, encountered some silk about two cm below the 
retreat and climbed directly to it. She touched the side of the 
