Gnats deposit their eggs to the number of 200, by each female, on stagnant waters where they are hatched into small grubs, in the course of two or three days. On the sides are four small fins, by the aid of which the insect swims about, and swiftly dives to the bottom. The larvae retain their form a fortnight, or three weeks ; when they are converted into chrysalis, in which state they continue three or four days, floating on the surface of the water, till they assume the form of gnats.
These insects have a cylindrical body, consisting of eight rings. The sting, which is perceptible to the naked eye, contains five or six spiculae, or darts, exquisitely minute. With these, gnats make punctures in the skin, and are supposed to inject a small portion of liquor which renders the blood circulating near the wound more fluid, and thus causes troublesome itch ing. Others observe, that female gnats only extract the blood by suction. As, however, these stings are generally attended with a painful swelling, different remedies have been suggested for its removal : one of the most effectual consists of small, but equal portions of Venice turpentine and sweet oil; they should be mixed and applied to the wounded part, which will be effectually relieved in the space of six hours. Indeed, olive oil alone, or unsalted butter, or fresh hog's-lard, if timely rubbed on the sting, will be equally efficacious. But we cannot approve of any mercurial solutions, that ha\e occasi-onally been advised in popular books, for the more speedy cure of this trifling affection.