I have observed

William EllisAgriculture Improv’d : or the Practice of Hudbandry, Londres, T. Osborne, 1746, p. 72.

Eighthly, Of Water-maggots, or Grubs. – I have feen various Kinds of thefe in ftagnante Waters, and particulary where there is Mud, and the Water fhallow. Here I have obferved a Maggot to gather Sticks, or Straws, or other Soil, and creep with it on the Ground till his Legs grew ufelefs, becaufe in this he inclofed himself, and bred Wings in the Hut of Houfe; and, at, laft, when he has got Strength enough, he crawls out of his Hut, takes Wing, and flies upon the Surface of the Water in the Summer. Firft it is called a Caddis, and then a May-fly.