184 INDIRECT INJURIES CAUSED BY INSECTS. 



saccharivora by Linne ; but, by making its nest for shel- 

 ter under the roots, so injures the plants that they be- 

 come unhealthy and unproductive. These insects about 

 seventy years ago appeared in such infinite hosts in the 

 island of Granada, as to put a stop to the cultivation of 

 this plant; and a reward of 20,000/. was offered to any 

 one who should discover an effectual mode of destroying 

 them. Their numbers were incredible. They descended 

 from the hills like torrents, and the plantations, as well 

 as every path and road for miles, were filled with them. 

 Many domestic quadrupeds perished in consequence of 

 this plague. Rats, mice, and reptiles of every kind be- 

 came an easy prey to them ; and even the birds, which 

 they attacked whenever they alighted on the ground in 

 search of food, were so harassed as to be at length un- 

 able to resist them. Streams of water opposed only a 

 temporary obstacle to their progress, the foremost rush- 

 ing blindly on to certain death, and fresh armies in- 

 stantly following, till a bank was formed of the carcases 

 of those that were drowned sufficient to dam up the 

 waters, and allow the main body to pass over in safety 

 below. Even the all-devouring element of fire was tried 

 in vain. When lighted to arrest their route, they rushed 

 into the blaze in such myriads of millions as to extinguish 

 it. Those that thus patriotically devoted themselves to 

 certain death for the common good, were but as the 

 pioneers or advanced guard of a countless army, which 

 by their self-sacrifice was enabled to pass unimpeded 

 and unhurt. The intire crops of standing canes were 

 burnt down, and the earth dug up in every part of the 

 plantations. But vain was every attempt of man to effect 

 their destruction, till in 1780 it pleased Providence at 



