Considering what was discussed on another thread, this may be interesting to some:

Quoted:

"

Ruddy Fly, Berners
FLY FISHING DICTIONARY
Midge Flies
upside-down fly?@?@English?@?sfly?t
?@ 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.
?yReference?zA 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.
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