STRAIGHT-WINGED INSECTS. 259 



ly destructive of all insects. Some species are occasion- 

 ally quite destructive in some parts of this country. But 

 it is in Asia and Africa that they appear in such immense 

 armies, leaving not a vestige of vegetation in their track, 

 eating the corn and the grass down to the roots, ancf 

 stripping the trees of their leaves. Mr. Gumming, in de- 

 scribing the flight of an army of these insects, says, " I 

 stood looking at them until the air was darkened with 

 their masses, while the plain on which we stood became 

 densely covered with them. Far as my eye could reach, 

 east, west, north, and south, they stretched in one un- 

 broken cloud, and more than an hour elapsed before their 

 devastating legions had swept by." These insects some- 

 times make incursions into Europe. One of these is de- 

 scribed by Professor Jaeger, who was an eyewitness of 

 it as he was traveling in Russia in 1825 across its desert 

 prairies. The carriage-wheels moved through Locusts 

 piled up to the height of two feet. This state of things 

 existed over a wide extent of country. The insects were 

 now wingless ; but the inhabitants of the fertile regions 

 north feared that, as soon as their wings were grown, 

 they would come north and devour every green thing. 

 Before this vast insect army could do this, the Emperor 



