INSECTS AND THEIR NEAR RELATIVES. 37 



ningthe thread 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. 



After making the outer framework the radiating lines 

 are formed. A line is stretched across the space so as to pass 

 through the point which is to be the center 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 fast- 

 ening another line there, it walk back to the outer frame- 

 work, and attaches this line an inch or two from the first. 

 In this way all of the radiating lines are drawn. The next 

 step is to stay these radii by a spiral line which is begun at 

 the center, and attached to each radius as it crosses it. The 

 turns of this spiral are as far apart as the spider can con- 

 veniently reach, except at the center of the web. All of the 

 threads spun up to this stage in the construction of the web 

 are dry and inelastic. The spider now proceeds to stretch 

 upon this framework a sticky and elastic line, which is the 

 most important part of the web, the other lines being merely 

 a framework to support it. In spinning the sticky line the 

 spider begins at the outer edge of the orb, and passing 

 around it fastens this line to each radius as it goes. Thus a 

 second spiral is made. The turns of this spiral are placed 

 quite close together, and the first spiral, which is merely a 

 temporary support, is destroyed as the second spiral pro- 

 gresses. Figure 41 represents a web in which the second 

 spiral is made over the outer half of the radii. In this fig- 

 ure, aa represents the temporary stay-line ; bb, the sticky 

 spiral ; and cc, the fragments of the first spiral hanging from 

 the radii. 



