: i ;S Rural School Leaflet 



head. Inside the beak are six slender, needle-like organs with which 

 the hole is drilled into the flesh of the person bitten; and the same 

 slender stylets serve as a sort of tube through which the blood is sucked 

 up into the mouth. 



Within the head of a mosquito there is a sac or gland containing a 

 fluid that acts like a poison on the blood of a human being. When the 

 mosquito sucks blood, it injects a drop of poison from this sac into the 

 wound. As a result there is much irritation and sometimes pain from a 

 mosquito bite, due to the presence of this poison in the wound. The 

 irritation from a mosquito bite varies greatly with different persons. 

 With some persons there is scarcely any burning or itching, while with 

 others swelling and inflammation occur, accompanied by severe pain. 



Methods of controlling mosquitoes. — The best way to get rid of mosquitoes 

 is to drain or fill up the ponds and pools in which they breed. Old tin 

 cans, pails, and the like, containing water, should be turned bottom side 

 up or drawn far away from houses. Rain barrels and tanks may be 

 covered with wire netting in order to prevent the mosquitoes from 

 laying their eggs on the water. 



In many cases ponds and pools that cannot be drained may be sprinkled 

 with kerosene oil every two weeks during the summer. The oil spreads 

 over the water in a thin film and prevents the wrigglers from obtaining 

 air through their breathing tubes. They are consequently drowned. 

 Moreover, the oil kills the eggs and prevents the female mosquitoes from 

 depositing more. In those pools and tanks that cannot be drained or 

 that it is not desirable to cover with oil, certain fishes may be intro- 

 duced which will destroy the wrigglers. Goldfish, sunfish, and certain 

 minnows will serve to keep pools free from mosquitoes. 



OBSERVATIONS FOR PUPILS 



i. Look on the tops of rain barrels and along the quiet margins of 

 brooks for the soot-like egg-boats of mosquitoes. If found, bring them 

 indoors and place them on water in tumblers or glass jars. Watch them 

 hatch and note the size of the wrigglers when they first come from the 

 eggs. Some of the mud and debris from the pool should be put into 

 the tumbler because in this material the wrigglers will find bits of food. 



2 . If the eggs cannot be found, bring in some wrigglers from a rain barrel 

 or a pool and watch them. They are very interesting in their movements 

 and habits. 



3. Note whether all the wrigglers are of the same shape and size. The 

 slender ones are the larvae and the ones with big heads are the pupae. 

 Study a larva first. What position does it take in the water? Note 

 the tiny tube that is thrust up to the surface of the water. This is the 



