Autumn Dun (Halford's)

Hook: 00 or 000 (These are size 16 and 17 respectively. I tied mine on a TMC 100 #18 hook, which is about a 17, maybe even closer to a 16. It was obvious to me that Halford wanted this fly to be small, as the BWOs are in the fall.) from F.M. Halford: "This is the dressing of the pale blue dun, so frequently seen during the autumn."
Body: Heron Herl undyed
Wings: Snipe
Hackle and Whisk: Palest blue dun. (The Whisk refers to the tail)