116 



NATURAL HISTORY OF ARTHROPODS. 



in the night. A single thread five or six inches long runs from the spider's roost, and 

 from its extremity radiate four branches attached to various twigs in the neighborhood. 

 Between the rays the spider spins the peculiar curled web, and then going back toward 

 its usual resting-place gathers up the slack of the single thread. The net is now set 

 for use, and she stands holding it till something touches it ; then she lets go with her 

 hind legs, and the net springs forward, bringing more threads into contact with the 

 insect. If she thinks it worth while she draws up another loop and snaps the web 

 again. When she is satisfied that the insect is caught she gathers up part of the web 

 till she comes to him, covers him with silk, and carries him up to her roost. 



Often in summer the bushes are covered with threads attached by one end, blowing 

 out in the wind, and bits of cobweb are blowing about with occasionally a spider 

 attached. To account for such threads curious theories have been thought of, among 



others that spiders are able to force the thread from their 

 spinnerets, like water from a syringe, in any direction they 

 choose. If a spider be put on a stick surrounded by water 

 si ie manages, in course of time, to get a thread to some 

 object beyond, and to escape by it. To find out how this 

 is done Mr. Blackwall tried some experiments. He put 

 spiders on sticks in vessels of water, and they ran up and 

 down unable to escape as long as the air in the room was 

 still. But if a draught of air passed the spider she turned 

 her head toward it, and opened her spinnerets in the op- 

 posite direction. If the draught continued a thread was 

 drawn out by it, which at length caught upon something, 

 when the spider drew it tight, and escaped on it. 



There is a still more curious use of this method of spin- 

 ning 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 pos- 

 sible, and there raise themselves up on tiptoe, and turn 

 their bodies up with their heads toward the wind and spin- 

 nerets open. A thread soon blows out from the spinnerets, 

 and if the current of air continues spins out to a length of 

 two or three yards, and then offers enough resistance to the 

 wind to carry the spider away with it up into the air. As 

 soon as she is clear the spider turns round and grasps the 

 thread with her feet, and seems to be very comfortable and 

 contented. Sometimes they rise rapidly and are soon out 

 of sight, at other times blow along just above the ground. 



This habit is not confined to any particular kind of 

 spiders, but is practised by many small spiders of the genus 

 Erigone, and by the young of many spiders of all families 

 that when adult would be too large for it. The best places 

 to watch them are garden fences, where they often swarm, 

 and can be more distinctly seen than on bushes. 



It is still unexplained how the thread starts from the spinnerets. It has been often 

 asserted that the spider fastens the thread by the end and allows a loop to blow out 



FIG. 165. Young Lycosa, about 

 to fly. 



