Insects are amongst the most active of creatures, whether for good or for evil, and the prodigious rapidity with which they increase under favourable circumstances would soon cause them to overrun the whole earth, to the extinction of almost every other creature, were these circumstances not controlled by an all-wise Providence, who keeps a constant check upon their progress by causing one insect to feed upon another, and who has formed almost innumerable other creatures (including birds, reptiles, and fishes) with instincts which lead them to feed upon insects in every stage of their development (fish devour the larvæ of many insects which inhabit the waters during the first stage of their existence); but it occasionally happens, when some of these salutary checks upon their increase are withdrawn, that they multiply with such fearful rapidity as to produce a complete famine, for they eat up everything before them. Who has not heard of the plagues of Locusts and the depredations of the White Ants? The swarms of Locusts in Africa will sometimes cover many hundred square miles of surface, and in this space not a vestige of any vegetation would remain after their visit. The description of the prophet Joel is sublime: "The land is as the garden of Eden before them, and behind them a desolate wilderness: yea, and nothing shall escape them.... The earth shall quake before them, the heavens shall tremble: the sun and the moon shall be dark, and the stars shall withdraw their shining." [Illustration: FIG. 21.--LOCUST (Locusta Migratoria).] But it is kindly ordained that these visitations shall only occasionally take place, and even when they do, terrible as is the infliction, a benefit in reality outweighing the injury often succeeds; for the land in these countries is often made almost barren by the quantities of tangled roots and stubble on the surface of the earth, which by the destructive powers of these insects is completely removed, and their manure left in its place, so that the fertility of the ground is much increased (often tenfold) after their visits. The thousands of species of insects which exist, render it impossible in a work like this, even to name them, but under the separate orders will be given a slight outline of the more important. [Illustration: FIG. 22.--THE STAG BEETLE (Lucanus cervus).] Insects are divided, according to the character of their wings, into nine orders. 1. COLEOPTERA (Black-winged).