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HANDBOOK OF NATURE STUDY 



but is occasionally injurious when it appears in large num- 

 bers. Of the migratory locusts, the Eocky Mountain locust 

 is probably the most destructive. Several times they have 

 almost caused a famine in a number of our Western states. 

 If your region was ever infested, let some old settler tell 

 you his grasshopper reminiscences, which will greatly inter- 

 est the children. 



The permanent home of these grasshoppers is in the 

 Rocky Mountains, and from that region they at times mi- 



FIG. 43. KOCKY MOUNTAIN LOCUST. 



Showing how the eggs are laid in the ground. Below, an egg mass taken 

 out of the ground ; to the right, five detached eggs. Natural size. 

 After Riley. 



grate in immense swarms as far east as Lake Winnipeg, 

 Minnesota, Iowa, and Missouri ; the frequency of their rav- 

 ages increasing as one approaches their permanent breed- 

 ing country. They do not, however, obtain a permanent 

 foothold away from their Rocky Mountain home, although 

 they do deposit eggs and appear in reduced numbers for 



Observations. Does it pay the farmer to keep his fields clean of weeds ? 



