A week or two ago the subject of the "Upside Down Dryfly" came up.
I think most of the important points got mentioned, by various
posters,
but this moroning I ran across the following link (actually a buddy
sent it to me).
This is a Japanese language site primarily, but it does have a
parallel set
of pages written in Englais. Note the earliest reference (1662)

http://www.kawanobooks.com/html/En/e081.html

upside-down fly　　English　《fly》
　 A fly in which the hook is used upside down.　As for the oldest
description of an upside down fly, Col. Robert Venables in Britain
mentioned such a fly in the "The Experienced Angler" (1662).　The fly
was a mayfly imitation that had the wing attached to the point side of
a hook.　At the time, many people imitated this pattern, and it was
also called reversed-wing.　Because the hook point is in the air in
this pattern, it can be effective to catch overly sophisticated trout.
However, hooking is said to be somewhat difficult.
　 In the 1970s, Brian Clarke and John Goddard of Britain introduced a
series of upside down patterns, and called it the USD series.　Later on
Neil Patterson made an outstanding fly pattern called Funneldun as an
improved version of USD series.
　 In the United States, Joe Brooks introduced the Keel Fly in his book
"Trout Fishing" (1972).　In Japan, upside down flies have been often
called keel fly or keel style, however because Keel Fly is a company's
name, upside down fly is more desirable for use in common expression.
【Reference】A dictionary of fly-fishing, 1993 (1992).　The experienced
angler, 1969 (1662).　The trout and the fly, 1980.　Trout fishing, 1972.
→Robert Venables, USD Paradun series, Funnel Dun, Joe Brooks, Trout
Fishing, keel fly