Spiders 



there to await the passing of the insect upon which it had 

 hoped to make a meal. 



From what we have already said, it is evident that, 

 though the sticky threads of the spider's orb will hold 

 a victim for a limited period, it is always essential for the 

 spider to lose no time in trussing its prey. We have 

 pointed out, too, that in reaching its prey the spider must 

 never touch the adhesive portions of its own orb. To 

 overcome this difficulty, one of our common spiders leaves 

 the space between two neighbouring spokes free of threads, 

 except for a silken line which it runs from the hub to its 

 hiding-place near by. When the signal runs along the 

 trap-line, as this single thread is called, the spider hurries 

 from its hiding-place and rapidly reaches the scene of 

 action via the sector devoid of sticky threads. 



There is a rare British orb-weaver whose snare is more 

 ingenious than those we have considered. It consists of 

 but four spokes and is only one-sixth of a complete orb ; 

 in outline it is roughly triangular. At the point from 

 which the four spokes arise the spider fixes a trap-line 

 which it leads to and affixes upon some solid support 

 near by. Now the spider converts this simple orb into an 

 ingenious spring trap ; taking up its position on the 

 under side of the trap-line with its head towards the snare, 

 the animal takes a firm hold of the line with its hind feet 

 and hauls in the slack with its fore-legs, till there is a con- 

 siderable length of trap-line lying between its fore and 

 hind legs. In this position the wily spider awaits her 

 prey. Immediately the vibrations of the trap-line show 

 that something is caught in the orb the spider releases its 

 hold with its fore-legs ; the snare, no longer held by the 

 tension on the trap-line, springs forward and the insect is 

 hopelessly entrapped. At least this is the eventuality 

 which the spider desires, but should failure to completely 

 enmesh the victim be the only result, the spider will 

 spring her trap again and again, till either the insect is 

 firmly held or makes good its escape. 



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