THE AERIAL WEB SPINNERS 181 



which may have been slung the egg sac. The habit is largely lost 

 by modern types, but some of the weavers have revived and ex- 

 tended it to produce striking patterns over considerable areas of 

 the web surface. It may be added that these bands, along which the 

 spider sometimes aligns its legs, doubtless give protection from 

 certain enemies. 



Recapitulating, the finished orb web consists of various distinc- 

 tive parts. A strong, moderately elastic framework, strengthened 

 by overspinning each line one or more times, holds in proper tension 

 a series of radial lines of dry silk. At the center is a thickened or 

 meshed hub, with or without extensive bands of silk, being the 

 strategic center of the web, the place where the spider hangs with 

 its claws touching the radii. Beyond the hub is usually a free zone 

 devoid of spiral lines; then comes the series of sticky spiral coils 

 that act to snare prey. The spider hangs downward or away from 

 the web, even when it is nearly vertical, and moves by grasping the 

 dry lines with tiny claws. The spider is anointed with an oil that to 

 some degree prevents the sticky lines from adhering to it. 



When an insect becomes entangled in the lines, the whole web 

 is agitated by the struggles, and the vibrations are communicated to 

 the spider. Quickly it swings across the web to the site of the dis- 

 turbance, directed by the pulls on the lines, all the while trailing 

 behind it a dragline thread, on which it can drop to the ground or 

 save a fall if brushed from the snare. Its long legs tap the prey, 

 further informing the spider of the nature of the victim, and bring- 

 ing on a response commensurate with the problem of subduing it. 

 Small, weak insects are seized and quickly enwrapped, but larger 

 and more active ones are treated with greater caution. The prey 

 is seized, held by some of the legs and turned round and round, 

 while it is trussed up with silk. Jets of fine filaments, thrown out al- 

 ternately by the spider's hind legs, are combed over the insect and 

 envelop it like a mummy. The bite may be administered either 

 during the capture or later, when the prey is caried back to the hub 

 and feeding begins. 



The struggling victim often cuts and entangles many spiral seg- 

 ments and radii, and may cause whole sectors to sag. During the 

 capture, broken lines are tied together with threads by the spider, 

 which deftly grasps the lines with its claws and pulls them together 

 around the rent. This effective repair of the web is carried out at 

 other times as well, by some species; still others allow the snare to 

 become a shambles. 



