FOES AND FRIENDS OF THE PLANT 



209 



will serve. We place in it some of the brown fruit flies which 

 may be caught wherever there is decaying fruit, and we lay a 

 piece of cardboard over the top. We can then see how they 

 lay their eggs on the blotting paper. In a few days the 

 eggs hatch, and the larvas (called maggots or worms) come 

 out. They will probabty crawl up the sides of the tumbler 

 and go into a resting condition (pupa), from which they come 

 out as winged flies. 



