226 INSECT LIFE. 



cation of the permanent spiral line (Fig. 193, b, b). 

 How do these two lines differ? What becomes of 

 the first line ? 



Throw an insect into a completed web and make 

 notes on the way in which the spider captures and 

 destroys its prey. If the web be that of one of the 

 larger orb-weavers, a large insect, as a locust or 

 grasshopper, can be used. 



Study different species of orb-weavers, and note 

 differences in the structure of their webs and in the 

 position of the spiders while waiting for their prey. 



Write an account of the habits of an orb-weaver. 



On dewy mornings the webs of the orb-weavers 

 are often heavily loaded with dew, so that adjacent 

 turns of the spiral thread adhere together. Fig. 194 

 represents such a web — one that the writer saw from 

 his window while at work on this book. 



BALLOONING SPIDERS. 



There are certain spiders that make long journeys 

 through the air like an aeronaut. These ballooning 

 spiders are frequently very abundant, especially in 

 warm autumn days. At such times innumerable 

 threads can be seen streaming from fences, from 

 bushes, and the tips of stalks of grass, or floating 

 through the air. The ballooning spider climbs to 

 some elevated point, which may be merely the tip of 

 a stalk of grass, and then, standing on the tips of its 

 feet, lifts its body as high as it can, and spins out a 

 thread of silk. This thread is carried up and away 

 by a current of air. When the thread is long 

 enough, the force of the air current on it is sufficient 

 to buoy the spider up. It then lets go its hold with 



