DISTRIBUTE INSECT VARIETY. '309 



blasts and in this way they will travel great distances. One was 

 captured off Cape Blanco, 370 oceanic miles from land, and 

 another I myself secured scudding on the trade wind 200 miles 

 by ship^s reckonings from Cape Palmas, on the same coast of 

 Africa. It is thus they become dependent on the winds for 

 distribution, and to the same cause they owe an uncertain ap- 

 pearance in Europe, or stragglers some autumns will waft north- 

 ward to our islands. Their terrestrial aggregation is due to 

 the workmgs of love and jealousy in their music, or coloration 

 as is probable. Their flocks often consist of more than one 

 species. Borne from their wintering-ground on arid plains or 

 barren momitains in seasons of dryness and sirocco, they alight 

 on the fragrant, well-watered lands of warmer climates, and 

 there deposit their ova. The larvae hatch when spring is yet 

 glowing in tender green, and then everywhere the canker-worm 

 is seen, in corn-lands, in orchards, in vineyards. These, treading 

 in the wake of the spring caterpillars, form into bands, and 

 advance, mowing and devastating with their jaws, like the 

 tearing harrow, crackling flame, or serried ranks of war, till the 

 first two stages of their voracious life are flown, and the winged 

 state approaches. Then, leaving their nympha cases on plant 

 and bush, they again flock together, animated by their newly- 

 acquired music, till of a sudden, rising like disembodied spirits 

 in a murmuring cloud that casts disastrous twilight, and yielding 

 to the impulse of the first airs, they waft onward for leagues 

 over sea and land, where'er they alight changing the summer's 

 landscape to a bleak and leafless image of northern winter, amid 

 the execrations, fires, and noises of the terrified inhabitants. 

 The assemblage then pairs. Nor is the plague stayed before 

 they leave their drowned carcases, dropped from the zephyrs, in 

 putrefying heaps along the tangle on the shore or margin of 

 lakes and rivers. So wrote a Syrian prophet, poet, and early 

 naturalist of the Migratory Locust, when rousing his depraved 

 countrymen to repel an Assyrian invasion ; and thus modern 

 travellers repeat the history of every such winged serpent they 

 meet with in Asia, Africa, or America. With respect to the course 

 which the Western Asiatic locusts pursue, Hasselquist has ob- 

 served the flocks migrate in a direct meridian line from south to 

 north, passing from the deserts of Arabia, which form the great 



