22 



PRACTICAL ZOOLOGY 



Mountain locusts, are of considerable economic importance, 

 appearing in some localities every year in such abundance as to 

 become very destructive to crops. Of these may be mentioned 

 the red-legged locust of the eastern United States (Fig. 7, A), 

 the California devastating locust in California, the differential 

 locust of the Mississippi Valley (Fig. 7, B), the huge lubber 



Fig. 8. — Two hopperdozers, tied together, at work. (After Lugger.) 



grasshoppers of Florida and the Western plains (Fig. 7, C), and 

 the American acridium of the Southern States. 



Several methods of controlling these non-migratory locusts 

 have been devised; fall plowing buries their eggs so that they 

 do not produce young; poison bran mash may be scattered in 

 the fields to kill both young and adults; and a contrivance 

 called a hopperdozer (Fig. 8) catches thousands of leaping in- 

 dividuals in its pans of kerosene as it is dragged over infested 

 fields. 



