LOCUSTS, OR GRAY GRASSHOPPERS. 409 



the kerosene emulsion will kill the bugs, but owing to their 

 numbers and habits it is hardly a practical remedy. 



Caloptenus many species. Locusts, or Gray Grasshop- 

 pers. 



Order Orthoptera. Family Acrididce. 



Although no grass insect is more serious in its destructiveness 

 than the Western locust, or grasshopper, Caloptenus spraetus. 

 Thorn., when it comes to make its presence felt, yet from the 

 fact that it can never attack the vegetation except in a limited 

 area West, and even there comes only rarely to scourge the coun- 

 try, it perhaps on the whole is not so serious to our forage crops 

 as the insects already referred to. Our common, red-legged 

 grasshopper, Caloptenus femur-rubrum, De G., with several other 

 species, often do very serious harm in our Eastern States. Yet 

 the fact that they come only rarely in great numbers, and then 

 scarcely ever two years in succession, makes the insect less 

 dreaded than it would otherwise be. 



FIG. 156. FIG. 157. 



Fig. 156 shows the Western locust, and Fig. 15 7 our red-legged 

 locust, which insects resemble each other very closely. The 

 principal difference is the longer wings of the C. spraetus. Like 

 the Chinch bug the transformations of these insects are incom- 

 plete. The larvae in early summer, the pupa in mid-summer, 

 and the imago in late summer all look alike, and have identical 

 habits as to their food. They differ only in size and develop- 

 ment of wings, which are at first wholly absent, and then appear 

 for a time only as stubs, or mere pads. The imago in August 

 and September lay their large eggs in the ground. In all stages 

 they are ravenous and indiscriminate feeders. 



Dr. C. V. Riley, in his elaborate investigation of this insect, 

 52 



