Insect Study 



381 



need for breathing, and they also take up from the water the poisonous 

 carbonic acid gas given oft" from the bodies of the animals. 



1. The aquarium should be kept where there is a free circulation of 

 air. 



2. If necessary to cover the aquarium to prevent the insects, like the 

 water boatmen and water beetles, from escaping, tie over it a bit of mos- 

 quito netting, or lay upon the top a little square of wire netting used for 

 window screens. 



3. The temperature should be kept rather cool; it is better that the 

 water of the aquarium should not be warmer than 50 deg. Fahrenheit, but 

 this is not always possible in the schoolroom. 



4. If any insects or animals die in the aquarium they should be 

 removed at once, as the decomposing bodies render the water foul. 



5. To feed the animals that live upon other animals take a bit of raw 

 beef, tie a string to it and drop it in, leaving the free end of the string 

 outside of the jar. After it has been in one day, pull it out; for if it 

 remains longer it will make the water foul. 



6. As the water evaporates it should be replaced with water from the 

 pond. 



References — The Fresh Water Aquarium, Eggeling and Ehrenberg; 

 Insect Life, Comstock; The Brook Book, Miller; Nature Study and 

 Life, Hodge- The Home Aquarium, How to Care for It, Eugecie S-mith. 



A humble, but useful, 

 aquarium. 



All inexpensive and durable aquarium. 



