The Natural History of Selborne

Most of our oaks are naked of leaves, & even the Holt in general, having been ravaged by the caterpillars of a small phalaena, which is of a pale, yellow colour. These Insects tho’ a feeble race, yet from their infiinite numbers are of wonderful effect, being able to destroy the foliage of whole forests, & districts. At this season they leave their aurelia, & issue forth in their fly-state, swarming & covering the trees, & hedges. In a field at Greatham a saw a flight of Swifts busied in catching their prey near the ground; & found they were hawking after these phalenae. The aurelia of this moth is shining, & as black as jet; it lies wrapped-up in a leaf of the tree, which is rolled round it, & secured at the ends by a web, to preven the maggot from falling-out.