Hans - I just did a quick Google search on "George Schlotter henwing fly" and found the following link. If you scroll down in the article, you can see a pattern called a "Henwing Emerger" (also known as March Brown Henwing Emerger/Pages 85 & 234/
Hatch Guide for New England Streams by Thomas Ames Jr.). According to Mr. Ames, George Schlotter's fly shop, The Angler's Nook, was for many years a fixture on the Battenkill in Shushan, New York.
http://www.thomasames.com/insects/artic ... spring.htm
If you read the article, there is a very interesting comment about how Mr. Ames fishes the henwing style fly. He writes "When the late afternoon hatch begins, I tie on one of George Schlotter's Henwing Emergers. By smearing floatant on the wing only, I can hang it in the surface film just like the clumsy natural, laboring to shed its shuck. Bigger fish often ignore the more exposed, high floating duns in favor of slightly submerged emergers." I need to remember this when I get to fish these flies.
