76 



THE FAMILY AQUARIUM. 



person while awaiting its metamorphosis into a winged 

 creature. With wonderful patience it collects very small 

 shells and stones to form its tube-like dwelling, which is 

 about the size of a wheat-straw ; and having cemented 

 them together, and rendered the whole quite smooth 

 inside, as well as at the bottom, he drags himself along 

 the bed of the tank, with his house about him, or else 

 adds a piece of light wood to his habitation, and floats 

 up nearer to the surface. 



The Diving Water Spider {Argyroneta aquaticus) dwells 

 in ponds and running streams, and is a particularly agree- 

 able inhabitant of the Aquarium. Its habits and appear- 

 ance are very remarkable. Although it lives at the bot- 

 tom of the tank, and is surrounded by water, it is never 

 touched by that element ! It is inclosed in a bubble of 

 air, which surrounds it like a silver box, and on the bed 

 of a stream may easily be mistaken for a globule of 

 quicksilver. Within that bubble the little creature per- 

 forms all his functions of eating, spinning, and sleeping. 



He lives, in fact, in a crystal palace, built for himself, 

 « 



as though he were the inhabitant of an enchanted castle. 

 This spider must not be placed in a tank containing fish 

 or other animals of the kind that consider him and his 

 shining raiment a honne louche^ or he will soon become 

 their victim. His tank, too, should be covered with 

 gauze. 



The Oniscus Aquatalis, and also the Hydrous Picens, 

 or Large Water Beetle, may, on the contrary^ be associ- 



