Stonefly adult
From The Basic Manual of Fly-Tying by Fling and Puterbaugh

Materials:
Hook: #4 – 14 dry fly 2x or 3x long
Thread: black
Tail bump: like olive dubbing
Tail: 2 moose mane or havelina hairs
Body: yellow floss
Wing: squirrel tail or deer
Front Hackle: 2 dry fly, one black, one brown or combination to match hatch 1.5x hook gape

Instructions:
Lay down a base of tread

Dub in a small lump at the hook bend to spit the tail fibers

Use two stiff fibers (moose mane, havelina) for the tail; tie one hair on the far side of the hook shank and one on the near side of the hook shank using the dubbing lump to spread them into a V; tie off and clip excess

   

Wrap thread to middle of hook shank and tie in floss to hook bend; use floss color to match local hatch; wrap thread back to two or three eye lengths behind eye; wrap floss in touching wraps to create the body; tie off two or three eye lengths behind eye

   

Stack a pinch of hair (squirrel tail, deer); measure from tie in point to end of tail; tie in on top of the hook shank; tie off and clip excess

   

   

Tie in two dry hackle feathers with barbs 1.5 hook gap length; wrap top feather to behind eye; tie off and clip; wrap second feather to behind eye; tie off and clip

   

   

Wrap head; whip finish; head cement