CHAPTER IX 



SHEET-BUILDING SPIDERS 



Habits of spider and character of snare — Refusal to spin in stormy 

 weather^Mode of capturing prey — Injection of poison — Sense of 

 touch — Function of pedipalps— Force of instinct — Shaniming death 

 in spiders and insects — Physical properties of web — Pertinacity of 

 Ariema. 



Every nook and cranny in these hills was used as a 

 lurking-place by another common genus of spider that 

 constructs its snare in the form of a non-viscid sheet. 

 This is the genus Hippasa, and the species most 

 probably H. olivacea of Thorell (see Plate, p. 88). 



The sheet of web, continuous with the funnel-shaped 

 tube at the mouth of which the spider waits in hiding 

 for its prey, is so well known as scarcely to need 

 description. The sheet is composed of such an 

 enormous number of tiny threads that at first sight it 

 seems incredible that the spider could lay down so 

 dense a network of single lines. After observing the 

 spider at the construction of its snare, it soon became 

 evident that, unlike the geometrical spider, it worked 

 with a bunch of filaments and not with a single thread. 

 After a scries of single foundation-lines had been 

 drawn from point to point so as to form a scaffolding 

 for the snare, the spider commenced to emit a sheaf 

 of filaments and to wander in a haphazard manner 

 backwards and forwards from side to side, attaching 

 the sheaf to suitable points until the fine sheet of 



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