300 FUNDAMENTALS OF AGRICULTURE. 



A MALARIAL MOSQUITO. 



cloth. Ditches should be kept free from water as 

 much as possible. To prevent being bitten by mos- 

 quitoes, dwellings should be well screened. 



EXERCISE. What enables a house-fly to stand on the ceiling? 

 How do you explain the ease which house-flies spread infection with 

 their feet? 



Require the pupils to bring some mosquito wigglers to school. Fill 

 two tumblers three-quarters full of water and place half the wigglers 

 in one tumbler and half in the other. Place a lantern globe (the top 

 of which has muslin tied on it) over one tumbler and watch the 

 development of the mosquitoes. Add enough coal oil to the other 

 tumbler to cover the surface of water and note the effect. 



