82 LIVING CREATURES. 



After finding so many odd features in the fly, it .need 

 not be surprising to learn that the young fly comes to 

 be full-grown in a wonderful way. The hen lays an 

 egg from which a chicken is hatched a small, downy, 

 feeble thing which in two years becomes an adult 

 fowl. The fly lays an egg that hatches, when behold ! 

 not a little fly, but a small, white worm or grub about 

 one third of an inch long. This thing the ancients 

 called a larva, which means a mask, because a real fly 

 was supposed to be hidden within. 



The fly's eggs are laid and hatched in the litter 

 which collects about the stable, or elsewhere. The 

 minute grub eats heartily for perhaps a week, and then 

 appears to die, and change into a shelly case. To this 

 little thing, quiet and motionless as a mummy, the 

 name pupa was given, which means a doll or girl. In 

 about two weeks this pupa splits open, when, not a 

 doll or a girl, but a full-grown, full-winged fly steps 

 out, dries its wings, and flies away, as if it knew all 

 about the world. 



After the great army of summer flies has been de- 

 stroyed by age, by fly-traps, and cool weather, a few 

 strong ones remain stupid, sleeping like woodchucks 

 and bears, until spring. Then, about the month of 

 May, the laying commences, a single fly depositing 

 several hundred eggs. These hatch, pass through the 

 changes described, and many of them, in turn, produce 

 eggs. The easiest way to be rid of the immense swarms 

 of summer is to destroy the spring mothers, which are 

 few. In the same way it is easier to strangle a bad 

 habit than to fight down all the wrong actions that 

 spring from it. 



