388 



THE WORLD OF ANIMAL LIFE 



When this important operation is completed, the spider lays 

 her eggs, which she places in a saucer-shaped cocoon, fastened to 

 the inner ' wall of her nursery. About one hundred eggs are 

 encased in this silken covering. She then mounts guard over 

 them, by resting just inside the mouth of the cell, with her head 

 downwards. 



Every now and then the parent spider seems to think that 

 a fresh supply of air is necessary. She therefore gives her nest 



Water Spiders 



a sudden tilt to one side, so that the exhausted air is turned out, 

 and floats up in a large bubble to the surface. Then, replacing 

 the little nursery in its former position, she quickly refills it in the 

 same manner as at first. This nursery also serves as a dining- 

 room ; for, whenever the spider catches a victim, she brings it down 

 to the cell before beginning to devour it. 



This is the only species of water spider known in the British 

 Isles, or indeed in Europe. Other species occur in other parts of 

 the world, and some few marine spiders are known. 



