WEAVERS OF ROUND WEBS. 



123 



perpendicular. The heavy spider hanging on the under side of the close 

 meshed hub pulled the net down at its centre as the snares were swayed 

 by the wind. The upper foundation lines were quite strong and usually 

 of great length, being from three to five feet, and in one case twelve feet 

 long. The orb itself is often about eighteen inches in diameter, and is a 

 conspicuous object to one driving by it upon the road. The concentric 

 spirals are numerous and placed in with great beauty and regularity. 

 They extend entirely around the snare, giving it a more circular appear- 

 ance than is common with 

 those webs which have 

 looped spirals below the 

 hub, thus giving the orb 

 an elongated form. For 

 the most part the hub is 

 closely meshed, but in one 

 case was found open. 



My own observation of 

 the snare of Gasteracantha 

 is limited to a single indi- 

 vidual seen in Texas in 

 the neighborhood of Aus- 

 tin. This web was spun 

 within a triangular space 

 of two feet or more in 

 length from top to bottom. 

 This space was marked off 

 by foundation lines, which 

 were decorated in a pecu- 

 liar manner, as represented 

 in Fig. 110. This decora- 

 tion consisted of tufts of 

 flossy white silk from one- 

 eighth to one-fourth inch 

 long. They were spread 

 along the outer foundation lines throughout nearly their entire length. 

 Several were also placed on the two inner supports of the orb. Two 



radii, one above and another below the centre, were similarly 

 Flossy decorated, and several tufts were grouped around the hub, which 

 w , was open. The number of these flossy tufts on one foundation 



line was twenty-one; on the other fifteen. The spider hung at 

 the centre of her web, which was vertical, and consisted of twenty-three 

 radii regularly crossed by spirals, many of which presented the deltated 

 appearance usually produced by the capture of insects. The figure here 

 given is drawn simply to indicate the exact position of the flossy tufts 



FIG. 110. Snare 01 Gasteracantha, to show the flossy tufts. 



