8o The Structure and Habits of Spiders. 



room was still. But, if a draught of air passed 

 the spider, she turned her head toward it, and 



9 



opened her spinnerets in the opposite direction. 

 If the draught continued, a thread was drawn 

 out by it, which at length caught upon some- 

 thing, when the spider drew it tight, and escaped 

 on it. If the air was kept still, or the spider 

 covered with a glass, she remained on the stick 

 till taken off. 



These experiments have been repeated, and 

 show that the spider does not shoot or throw 

 the web in any way, but takes advantage of 

 currents of air, and allows threads to be blown 

 out to a considerable distance. 



There is a still more curious use of this 

 method of spinning threads ; that is, in flying. 

 Small spiders, especially on fine days in the 

 autumn, get up on the tops of bushes and 

 fences, each apparently anxious to get as high 

 as possible, and there raise themselves up on 

 tiptoe, and turn their bodies up, as in Fig. 40, 

 with their heads toward the wind, and spin- 

 nerets open. A thread soon blows out from 

 the spinnerets, and, if the current of air con- 

 tinues, spins out to a length of two or three 



