342 



AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



Genesis of. 

 Snares. 



any relation to other species of its tribe. Yet it is certainly interesting 

 to observe the varieties of use to which this implement has been placed, 

 and to observe that a seemingly rudimentary implement and incidental 

 service in one species, as Epeira strix or Epiblemum scenicum, become in 

 another and widely separated species a special instrument and a complex 

 and permanent habit. 



II. 



In the foregoing section we have traced the connection between the 

 primitive dragline and the traplines by which snares are operated, and 



^have noted the relations or points of resemblance 

 between the various forms of trapline among Orb- 

 weavers, from the simplest to the most complex. 

 We may now attempt a like service for the entire sys- 

 tem of trapping spinningwork known as 

 the snare. In this undertaking I propose 

 to go beyond the field of orbwebs, and 

 take into the view the characteristic snares 

 of all the aranead tribes. 

 Let us suppose, again, that the original form of spinningwork was the 

 single line which has been alluded to as the dragline, and whose relation- 

 ship we have just traced into the various forms of snares made 

 The Origi- ^ v Qrbweavers. If now we venture further to suppose that the 

 ihia-work s P^ er a l wa y s possessed the habit which is strongly apparent in 

 such tribes as the Lineweavers and Orbweavers, of moving rest- 

 lessly to and fro between twigs and leaves, spinning out a single thread, 



FIG. 332. 



The original spinning thread 

 the dragline, a. 



FIG. 333. The meshed snare of Theridium, thickened at the top, and supported by 



silken trestles. 



and making anchorages and attachments as it moves (Fig. 332), we easily 

 arrive at the form of snare characteristic of Lineweavers. 



These straggling lines, crossed at all angles, would soon, and without 



