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[Vol. 87 
single horizontal thread is similar to a Pasilobus web: if one 
breaks the low-shear joints at the ends of Pasilobus spanning 
threads so that they hang from the midline, the webs are nearly 
identical. The web of Cyrtarachne sp. (Fig. 18) is very similar to 
that of Poecilopachys, as is its building behavior (Eberhard, 
unpub.). 
C Both M. dizzydeani females and Pasilobus catch moths almost 
exclusively. This specialization in M. dizzydeani is probably 
due to the use of moth sex attract pheromone mimics (Eberhard 
1977), and it is possible that the same may be true for Pasilobus 
(Robinson and Robinson 1975). It is interesting to note that the 
tendency of Pasilobus to lay the frame lines by floating them 
downwind of the spider’s eventual resting site would make its 
nearly horizontal web lie downwind of the spider, and at least as 
long as the wind direction did not change this would be the 
direction from which moths being attracted chemically would 
be expected to approach. 
D Both M. dizzydeani and Pasilobus produce sticky silk which 
adheres firmly to moths, something which no other araneid is 
known to do. Their sticky silk seems to differ in that Pasilobus 
silk will stick repeatedly while that of M. dizzydeani loses most 
of its stickiness after the first contact. 
E Both M. dizzydeani and Cyrtarachne sp. release an unpleasant 
odor when handled, a characteristic unique among araneids 
and perhaps all spiders. Species of all four genera rest in very 
exposed sites during the day with their legs folded tightly 
around their bodies so their front legs cross under the anterior 
part of the cephalothorax, a posture unusual in araneids. 
In addition to these links between M. dizzydeani and Pasilobus, 
Poecilopachys, and Cyrtarachne, there are also behavioral links 
between M. dizzydeani and Celaenia and Taczanowskia: 
A All three seem to specialize as adults on male moths as prey 
(McKeown 1952, Eberhard in press). Capture of small flies by 
spiderling M. dizzydeani is also parallelled in Celaenia sp. since 
C. S. Lauder has found over 300 spiderlings of this species 
feeding — all on male psychodid flies (C. S. Lauder, pers. 
comm.). 
B Both Celaenia excavata and Taczanowskia sp. (Eberhard in 
press) seem to spin no web other than a single dry horizontal 
