to a chrysalis, the skin dries round it, and i assumes an oval form, of a reddish colour, which, lit ten days more, produces the pcr fect fly.

The fourth genus is Tabanus. These insects are nourished with the blood of horses and cattle. During the summer heats, especially in the middle of the day, they are extremely troublesome, piercing the skin of large animals with the lancets of their trunk, in order to suck the blood; which causes such intolerable pain, that the cattle gallop about as if they were dis tracted. They abound most in damp woods and meadows. The largest of the British

species is the Tabanus bovinus, or great Uorsc

fly. It is sometimes inch long, and is of a greyish colour, marked down the back by a row of white, triangular spots.

The Tabanus pluvialis is about the size of a window-fly, of a dullish brown, the wings marbled with numerous whitish specks; and is a troublesome companion in autumn, iar .ticularly on the pproac1i of rain, as it bites any part of the flesh which is uncovered.

The diffirent species of that tormenting in sect, the Gulex, or Gnat, form the next genus. Their larvin are very frequent in standing waters. Nine segments, diminishing in size and length from the head downwards, compose

their