Allan your tutorials are excellent, and the response to this thread has been great- thankls for doing this!
We have a lot of very talented tyers out there.
I love tying and fishing flymphs-- here's one I use for the early spring Hendrickson mayfly hatch here in the East:
I tie and hackle them a little differently- here are the materials in order of tie in, and description of the tying steps I use:
Hook: Mustad size 10 3399 here
Thread: 8/0 Claret
Hackle: Medium dun hen saddle feather here, tied in by base, dull side up, feather left extending out over eye
Tail: Medium dun hen saddle barbs
Rib: Fine gold wire
Abdomen: Dark brown rabbit dubbing (the color of the Hendrickson nymphs), then ribbed with the wire
Thorax: Dark brown rabbit dubbed to eye and back to 1/3 point to make a double layer of dubbing. Leave thread hanging at 1/3 point and wind hackle 3 turns back towards tying thread. Weave tying thread through hackle to eye to lock it down, form thread head and tie off.