236 Destructiveness of Insects. 



while thus enclosed, this cocoon bursts open, 

 and out comes a beautiful Butterfly, changed 

 from what was, only a short time before, a slow, 

 crawling, and repulsive looking Worm. 



8. So, you see that the forms and changes of such 

 Insects are ist, the Egg; 20!, the Worm, Grub or Cater- 

 pillar ; 36, the Chrysalis ; and 4th, the Butterfly, or perfect 

 Insect. 



9. Some kinds of Insects are very trouble- 

 some and often do great damage to trees and 

 plants. You all know how soon one or two 

 Caterpillars can eat up all the leaves of a little 

 plant or bush in your garden, and that swarms 

 of GRASSHOPPERS or LOCUSTS have in a few 

 hours eaten up acres upon acres of growing 

 corn, besides grass and vegetables. 



10. The increase in the numbers of Insects is 

 wonderfully rapid; indeed, if it were not for 

 the multitudes of the busy birds whose food 

 consists wholly or mainly of Insects, man might 

 be unable to prevent the entire destruction of 

 his orchards and his crops. 



11. Great numbers of Insects are devoured by other 

 Insects, and also by Toads, Frogs, and Ground Moles. 



12. You must not think, however, that all 

 Insects, Caterpillars and Butterflies are our 

 enemies, for there are some kinds that are con- 

 stantly at work for us. 



