EXERCISE 111 



Problem. How do eggs of mosquitoes change into adults ? 



What to use. Glass jar or tumbler ; cheesecloth ; large magnifying glass. 



What to do. Get some fresh pond water ; have glass about two-thirds full. 



;ave water in glass exposed out of doors overnight ; in the morning examine 



le surface of the water for mosquito eggs. If any are found, cover glass with 



icesecloth. Then study with magnifying glass from day to day to note changes 



lat take place. 



Record. Make drawings to illustrate the changes noted. Describe move- 

 icnts of larvae etc. 



Questions. 1. How many eggs were there? How many hatched out? 



2. How can you tell whether the mosquitoes that hatch out in the glass are infected with malaria 

 some other disease parasite ? 



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