COLLECTING AND PRESERVING INSECTS BANKS. 



11 



Acridiidse) have short antenna. The two other groups have exi remely 



long and many- jointed antennse, and 

 also differ from the grasshoppers in 

 having a prominent ovipositor. 



The grasshoppers (figs. 13, 151) (or 

 locusts), as is well known, are often 

 very destructive to crops. They usu- 

 ally deposit their numerous eggs be- 

 neath the soil in late summer or 

 autumn, the young hatching in the 

 spring and feeding on the adjacent 

 vegetation. Some species, as the 

 ''Rocky Mountain locust," at times 

 become so numerous that they are 

 obliged to migrate to obtain food. 

 These migrating swarms were for- 

 merly a tremendous scourge to the 

 western farmers, but now their breed- 

 ing grounds have been largely de- 

 stroyed by cultivation. Grasshoppers 

 are more numerous in species in the 

 prairie regions than elsewhere in the 

 country. Several species can make 

 a noise by their wings when in flight. 



Quite a number of meadow locusts 

 and katydids (family Locustida?) are predaceous and feed on plant- 

 lice or other small insects. They are commonly green in color, and 



Fig. 14.— The katydid, Cyrtopuyllvs per- 

 spicillatus. 



Fig. 15.— A mole-cricket, Scapteriscus dida< 



TYLUS. 



Fig. 16.— A tree-cricket, Orocharis saltatoh : 



a, Female; b, male. 



occur on shrubs or in grass, where I hey are not readily not iced. The 

 males of all the species can make sounds by rubbing the base of one 



