330 



INSECT LIFE. 



combining a large lamp-chimney with a small flower- 

 pot (Fig. 289). 



AQUARIA. For the breeding of aquatic insects 

 aquaria are needed. As the ordinary rectangular 

 aquaria are expensive and are liable to leak, we use 

 glass vessels instead. 



Small aquaria can be made of jelly-tumblers, glass 

 finger-bowls, and glass fruit-cans, and larger aquaria, 



of the form shown in Fig. 

 291, can be obtained of some 

 dealers. A good substitute 

 for these is what is known 

 as a battery-jar. There are 

 several sizes of these, which 

 can be obtained of most deal- 

 ers in scientific apparatus. 



To prepare an aquarium, 

 place in the jar a layer of 

 sand ; plant some water 

 plants in this sand, cover the 

 sand with a layer of gravel 

 or small stones, and then add 

 the required amount of wa- 

 ter carefully so as not to dis- 

 turb the plants or to roil the water unduly. The 

 growing plants will keep the water in good condi- 

 tion for aquatic animal life, and render changing of 

 the water unnecessary, if the animals in it live natu- 

 rally in quiet water. Among the more available 

 plants for use in aquaria are the following : 

 Water weed, Elodca canadensis. 

 Bladderwort, Utricularia (several species). 

 Water-star wort, Callitriche (several species). 



FIG. 291. 



