WATEK SPLDEKS. 261 



If seen on land there is nothing about the creature to 

 attract attention. It is not larger than a fair-sized 

 garden spider, though its legs are rather long in pro- 

 portion to its body, and the colour is dark blackish 

 brown. Both the abdomen and legs are thickly coated 

 with hairs, but with this exception there is nothing in 

 its external character to denote the life which it is 

 intended to lead. 



These apparently insignificant hairs, however, enable 

 the spider to supply itself with air, and the mode in 

 which it does so is very remarkable. 



The creature goes to the surface of the water and 

 moves all its legs very busily, just as if it were trying to 

 crawl out of the water. Suddenly it gives a sharp jerk, 

 or kick, and dives below the surface. It then looks 

 exactly as if it were surrounded by a case of polished 

 silver, owing to a bubble of air which it has enclosed 

 between its long hind legs. On account of this silvery 

 aspect the Water spider is called scientifically Argyronetra, 

 aquatica, i.e. Aquatic Silver-spinner. 



Besides the large bubble of the hind legs, there are a 

 number of smaller bubbles which cling to the other legs, 

 and which can be added to the principal bubble when 

 needed. This supply of air is sufficient to last the 

 spider for a considerable time ; but there comes a 

 period when it will have to furnish air for others besides 

 itself. 



The best plan of watching the proceedings of the 

 Water spider is to place it in a glass vessel, taking care 



