The Beaverkill is one of the most recognizable classic Catskill dry flies. Yet it started as an English wet fly before transforming into a dry fly.
"... was cast upon Catskill waters long before the Dettes were even born. We know from his brochure fly pattern listing that William Warren Cone, in the 1880's, featured a pattern bearing that name. But historical texts also remind us that the Beaverkill was first tied around 1850.
A Greene County, NY (a Catskill county) judge named Fitz James Fitch gave a similar British pattern to Harry Pritchard who first tied the fly. It was Fitch who named the fly after his beloved Beaverkill River. Harry Pritchard and his brother Thomas operated a sportings goods store at 50 Fulton St., in New York City. Harry was known as one of the greatest fly casters back in his time. Harold Hinsdill Smedley's classic book Fly Patterns and Their Origins (1944) tells us that "the fly as originally tied was similar to the present male or Mr. Beaverkill. Mr. Pritchard's pattern called for dressing with light body and gilt strip ribbing, brown hackle and mallard wings."
-The Beaverkill, in both wet and dry fly form, was also show cased in ca. 1920's Wm. Mills & Son catalogs. It is also interesting to note that as was common with many early Catskill trout flies---given their British influences---the pattern was tied with gray mallard fiber tails (not hackle barbs); wings were sometimes tied with blue heron, pidgeon or the more common mallard duck quill slips that we use today. In his Streamcraft (1917), George Parker Holden featured the Beaverkill by dressing:
Wings: blue heron or slate colored wings of duck or pidgeon
Body: white silk
Hackle: brown
Tails: gray Mallard
And, of course, Rube Cross listed the pattern as we now love it; White body, gray wing, brown palmer hackle, brown hackle tail.
And, doubly of course, Mary Orvis Marbury (Favorite Flies and Their Histories) gives greatly expanded details concerning the pattern's history and Pritchard's story. (Plate #105 illustration). It's highly probable that Smedley obtained his information from Marbury's reference book. However---the illustration looks nothing like what we would call a "Beaverkill,"--check out the wings. And, that featured was a wet fly pattern."