Note 1 — Letter XXIV
Reading edition
The angler’s may-fly, the ephemera vulgata Linn., comes forth from its aurelia state, and emerges out of the water about six in the evening, and dies about eleven at night, determining the date of its fly state in about five or six hours. They usually begin to appear about the 4th of June, and continue in succession for near a fortnight. See Swammerdam, Derham, Scopoli, etc.