from εφέμερος, "a day;" a diary fever, or fever of one day's continuance only. In this case, such a heat as attends an excess of wine, a pulse somewhat full and quick, but soft and regular, a slight head-ach, a nausea, and restlessness, are all the symptoms, and which terminate without any sensible evacuation. If it continue unto the third day, it is not a diary fever; and if the constitution is very dry, an hectic is to be dreaded.

the Day-Fly, in zoology, a genus belonging to the order of neuroptera. It has no teeth or palps; there are two large protuberances above the eyes; the wings are erect, the two hind ones being larger; and the tail is bristly. There are 11 species, distinguished by their colour and the number of bristles in their tail. This fly derives its name from the circumference of its living but one day. They are seen flying about the surface of the water in mid-summer, for three days, and no longer; they eat nothing, and their only business is to drop their eggs on the water after they have copulated. These eggs sinking to the bottom, produce a sort of worms or maggots; these soon hollow themselves cavities in the clay, where they remain three years, growing every year about an inch in length. When the worm is come to its full growth, it rises to the surface of the water, about six o'clock in the morning; and there issues from it this fly, which lays its eggs, and dies, about six o'clock the same night: so that the life of the creature in the fly-state is only about 12 hours.