544 Our Surroundings 



and leave particles of filth that are often laden with germs of 

 disease. 



Flies possess some remarkable structural adaptations which 

 make them very alert. They have large compound eyes that 

 move freely from side to side, making them keen observers. 

 Thanks to their membranous wings they are rapid movers. Their 

 mouth parts are so made that they form a proboscis, or feeding 

 tube, well adapted for both lapping and sucking food. Their 

 feet have pads on which tube-like hairs develop that secrete a 

 sticky fluid. Thus they are able to walk as readily on the ceilings 

 and walls of our homes as on the table. This fact enables them 

 to leave germs of disease not only on our food, but in all parts of 

 our rooms. It is possible for them to bring into our homes not 

 only typhoid germs but also germs of tuberculosis and other dan- 

 gerous diseases. Hence the need of getting rid of them. 



How to Get Rid of House Flies. There are several ways of 

 getting rid of house flies, such as by dishes of poisonous liquid, 

 sticky paper, and traps. Screens will keep them out of the 

 house and away from food. By far the best method of control 

 yet found, however, is the removal or destruction of their breed- 

 ing places. It seems hopeless wholly to exterminate them, but 

 their multiplication can be controlled. Every one should encourage 

 the destruction of the places where they grow and develop. 

 Manure heaps and all garbage and excretions of every kind should 

 be removed from the vicinity of homes. Such action will do much 

 to get rid of the fly nuisance. 



SUMMARY 



The interrelation of plants and animals in the world may be 

 understood by the study of life in a balanced aquarium or ter- 

 rarium. 



Green plants are the makers of food and so render service 

 both to other plants and to animals. Animals and non-green plants 

 break up food into elements and compounds that are again used 

 by green plants. 



In their relation to plants and to man some insects are beneficial 

 and some harmful. The same is true of birds. 



