1971] 
Robinson Mirick — Nephila clavipes 
137 
evoke this behavior gave results which are entirely consistent with 
this view. In fact increasing the weight of the prey eventually 
results in the suppression of attack behavior and its supercession by 
escape. We obtained evidence that N. clavipes would lose some 
large prey by escapes, during the prolonged process of a bite & 
back off attack. Prey of similar size presented to the much smaller 
Argiope argentata were not lost during wrapping attacks in any of 
our presentations. (The senior author has obtained similar results 
in comparing the performance of Nephila maculata and Argiope 
aemula ( Walckenaer) , dealing with large acridiids and melo- 
lonthid beetles.) We have also recorded injuries inflicted on N. 
clavipes during biting attacks on prey that had biting mouthparts 
and have one record of injury following the defensive kicking of 
an acridiid. The economy in time spent at the capture site that 
is a potential consequence of attack wrapping was examined in detail 
by Robinson, Mirick & Turner (1969), who suggested that a major 
factor in this economy was the ability of the spider to leave an 
attack-wrapped prey in situ after delivering a short bite. These 
authors argued that once the prey was wrapped the spider could 
safely leave it and not transport it to the hub until the bite had 
taken effect. With biting attacks, on the other hand, the bite could 
not be terminated until the prey had been safely subdued by its 
effects. The economy in time that results from this process is greatly 
exaggerated if one compares time spent in bite & back off attacks 
with time spent in wrapping attacks on similar prey by other spiders. 
(This comparison will be made in the projected comparative paper; 
it was not made by Robinson, Mirick & Turner (ibid) because 
the data for the attacks of Argiope species on very large prey was 
not then available). 
It is interesting that although N. clavipes wraps prey at the capture 
site it does not store them there. Once this type of wrapping be- 
havior has evolved it would seem but a short step to utilize it to 
enable the spider to interrupt the predatory process after the attack 
phase and defer the removal of the prey from the web, and its 
transportation, until later. This step, according to Robinson, Mirick 
& Turner (ibid) would be advantageous in circumstances where 
large numbers of prey arrived in rapid succession, or where prey 
left at the hub during an attack might be in danger of being stolen 
by kleptoparasites in the absence of the spider. At the time these 
authors suggested that N. clavipes may transport all prey to the 
hub because the depredations of kleptoparasites might be more diffi- 
cult to detect if prey were stored at a number of capture sites in a 
