Spiders 



called a cribellum for spinning this decorative silk. The 

 cribellum is a plate, situated in front of the foremost pair 

 of spinnerets and perforated with a number of very fine 

 holes. From the pores of the cribellum the finest of silk 

 issues and, as it does so, it is carded and distributed into 

 the lace-like bands of the web, by means of fine combs 

 situated on either hind leg of the female spider. 



Strange as it may seem, the cobweb-spider has a near 

 relative of aquatic habits, the common water-spider. 

 Frequenting ponds and slow-running streams in plenty, 

 the water-spider and its ways may easily be observed. 

 The female spins a web as beautiful as it is ingenious, 

 a web designed to serve as her boudoir and not as a trap 

 for prey. Having found a suitable water weed, the mother 

 spider proceeds to spin silken threads loosely from branch 

 to branch, or from leaf to leaf. These threads form at 

 once foundation and guy ropes for her future home, for 

 on them she weaves a closely woven web which is at first 

 horizontal. Having completed her building operations, 

 her next care is to fill her home with air ; this she does by 

 ascending to the surface of the water, when air is entrapped 

 about her hairy body. With the captive bubble, which she 

 often encircles with her hind legs for greater security, she 

 swims below her web ; then with her hind legs she kicks 

 her burden free. This operation she repeats again and 

 again, with the result that the web, originally flat, becomes 

 thimble-shaped by reason of the contained air. 



The female spider hunts her prey on the surface of the 

 water and, having made a capture, returns with it to her 

 thimble-shaped home. Towards the end of summer the 

 mother spider's boudoir is converted into a nursery ; the 

 eggs are laid in the upper part of the dwelling and a wall 

 is built across the shelter to prevent the inmates from fall- 

 ing out. Having completed her labours, the mother spider 

 retreats to the deeper water, where she spins a very similar 

 though more densely woven shelter in which she retires 

 for her winter rest. When the young water-spiders 



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