14 
Psyche 
[March 
capture thread after wrapping the prey instead of re-attaching it to 
the dragline. In these trials, the spider did not rotate-wrap the prey, 
but cut it out after the initial wrap and carried it directly back to 
the resting thread. In all three trials, the ants were carried up to 
the resting thread dangling from the spinnerets on a 1.5 to 2 cm 
thread which was held with one or both legs IV. After reaching the 
resting thread, the spider pulled the prey in with legs IV and rotate- 
wrapped it. 
Live moths of about the same length as the spider escaped readily 
from the capture thread by fluttering down it, leaving behind a con- 
spicuous trail of scales stuck to the cribellar silk. We observed four 
complete prey capture sequences with moths and saw no major 
modifications in prey capture behavior, such as those seen with 
some araneids (Robinson 1969, Robinson et al. 1971). In three of 
the trials, the spider discarded the remaining capture thread after 
wrapping; as with the ants as prey, the rotate-wrap stage was 
omitted from these captures. 
These observations suggest that the decision to retain or discard 
the remaining capture thread is made early in the attack sequence, 
and is perhaps related to the size of the prey. If the capture thread 
is to be abandoned, it may be advantageous for the spider to delay 
rotation-wrapping until it reaches the resting thread, where it is less 
exposed to visual predators. This explanation is not entirely satis- 
factory, however, since if rotation-wrapping is not necessary at the 
capture site (it would seem most necessary for just those large prey 
for which it is omitted), it would seem advantageous to perform 
all rotation-wrapping at the more protected resting thread. 
Capture sequences with multiple prey 
Capture of small prey such as fruitflies caused little damage to 
the capture thread, because the repair of the thread left the remain- 
ing sticky portion intact. When presented with a second or third 
prey, the spider rushed down the capture thread holding the first 
prey in its palps, and attacked the new prey in the usual manner. 
Second prey were wrapped together with the first prey and carried 
up to the resting thread in the palps in one large package, or 
wrapped separately and carried up hanging from the spinnerets, 
then wrapped with the first prey. 
After only a few prey items were captured, the spider destroyed 
the remaining capture thread by dropping the lower end of the 
