No. 1 The Blue Dun
This fly is the earliest American ephemera, and may be found on warm days in February. In March it is abundant. It lives three or four days, and then becomes the red spinner.
Imitation.
Body.—Mouse-colored mohair, spun very thinly on yellow silk.
Tail.—Two fibres of gray mallard.
Wings.—From a quill-feather of the robin’s wing. The third or fourth feather with a tinge of reddish brown at the extremity of the fibre.
Legs.—Two or three turns of a blue or ginger dun hackle. One side of the hackle may be stripped off for the ephemeridæ.