The Life of Spiders 



to it; the spider then pulls the line tight, and fastens it where 

 it is standing. It then has a bridge along which it can easily run. 



The foundation lines. — Having constructed this bridge, which 

 is usually strengthened by passing back and forth over it and 

 adding a dragline to it on each trip, it is easy for the spider to 

 stretch the other lines that are to serve as the outer framework 

 of the web. In doing this it fastens a thread to one point, and 

 then walks along to some other point, spinning a dragline as it 

 goes, and holding it clear of the object on which it is walking 

 by means of one of its hind legs. When the second point is reached 

 the thread is pulled tight and fastened in place by an attachment 

 disk. 



If it is desired to spin a second bridge below one already made, 

 the spider has only to fasten a line to a point below one end of 

 the first bridge and then walking up the supporting object, and 

 across the bridge, and down the other support to the right point, 

 spinning a dragline as it goes; this is then pulled tight and fastened; 

 and a second bridge is formed; between these bridges the orb 

 can be built. To complete the outer supporting framework of 

 the web other lines are stretched in a similar manner between the 

 bridges and from them to the supporting objects. These are 

 placed in such a way as to leave an open space, more or less ir- 

 regular in outline, in which the orb is to be built. The lines 

 forming this framework have been named the foundation lines. 



The radii. — After making the foundation lines, the radiating 

 lines of the orb are formed. The first step in this operation is 

 to stretch a line across the open space in the framework so as 

 to pass through the point which is to be the centre of the orb. 

 In doing this the spider may start on one side, and be forced to 

 walk in a very roundabout way on the outer framework to the 

 opposite side. It carefully holds the new line up behind it as it 

 goes along, so that it shall not become entangled with the lines 

 on which it walks; one or both hind feet serve as hands in these 

 spinning operations. The spider then goes to the point where 

 the centre of the orb is to be, and fastens another line there, it 

 then walks back to the outer framework spinning a line as it goes 

 and holding the new line clear from the one on which it is walking; 

 the new line is fastened to one of the foundation lines. In this 

 way all of the radiating lines are made, the spider returning to 

 the centre of the web to begin each radius. In some cases at 



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