To stop the ravages of caterpillars in some forests trenches have had to be dug. Into these they fall as they pour forth “in serried columns,” after having devoured one section of a wood, when on their way to attack a sound part. In the trenches they are stifled by numbers of men heaping earth on them. Sometimes great trees in the forest have to be set on fire as the only way of stopping their ravages. Then there are concealed foes who hollow out galleries in trees before their presence is suspected. One little insect has been dubbed by a naturalist with the formidable name of “the great pine-gnawer.” It ravages forests of fir-trees in such wise that not a single tree escapes its attacks. Stag-beetles haunt our oak-trees, bruise the bark, and then lick up the sap, and in its larval stage this beetle feeds in the solid wood of the finest trees, keeping near the bark. We read also of the antler moth flying “in countless myriads.” In Galway in 1868 cockchafers arrived in hosts, forming a dense cloud which darkened the sky for a distance of three miles. “The whole country at midsummer assumed the appearance of winter. The noise of their innumerable jaws sounded like the sawing of wood, and the buzzing of their countless wings filled the air with a sound like the distant rolling of drums.” And to add to the misery of this appalling picture, the famine-stricken Irish were then “driven to eat them in order to support life”! Whole fields of turnips are often cleared, that is, the leaves of the plants are stripped off, by myriads of the turnip fly or beetle that come flying unexpectedly, one knows not whence. It was estimated that the loss through this to one county in a single season was once £100,000, and Miss Ormerod states that in 1881, when there was an invasion of the turnip fly, spreading nearly all over our country, the loss amounted to considerably more than half a million. A prince in Bohemia once employed two hundred men for four days and a half in collecting caterpillars during a plague of these, and they gathered twenty-three bushels of them, which they reckoned amounted to 4,500,000 of these creatures. In the year 1574 cockchafers gathered in such numbers on the banks of the Severn that the water-mills were stopped working. Miss Edith Carrington, who has written many useful little books on out-door life, has lately brought out one called _The Farmer and the Birds_, in which she has collected many valuable facts and statistics which would be of interest to you. Think of the size and the weight of one of these cockchafers, and then ponder again on what can be effected by persistent co-operation. And if for evil, yet also for good. That is our lesson just now.