Note: This recipe has not been verified against a documented source, or disagrees with one. Treat the materials and steps as unconfirmed.
The Orvis Company dressing
Hook 3XL nymph or 2XL dry fly hook, 4-12
Thread Black (140 denier 3/0
Materials
Body Peacock herl
Wing Pearl Krystal Flash and white Ultra Dry Yarn or Para Post
Legs Black and white barred silicone legs
Hackle Black saddle hackle
How to tie it
Run a thread base from the eye back to the bend.
Bind a strip of 2mm black foam at the bend, pull it forward, and lock it down at the 45% mark to form the rear hump (the fat gaster); optionally dub a thin waist here.
Figure-8 three strands of black rubber leg across the shank at the waist so they splay out each side; trim later.
Pull the foam forward again and bind it behind the eye to form the front hump (head/thorax); do not crowd the eye.
Post a short tuft of white or pink poly yarn upright over the thorax as a visibility indicator.
Whip finish under the front hump, trim the legs to about a gap-and-a-half, and cement the tie-down points.