Sulphur

[letumgo]

Interesting observation, Carl. I went back and looked at the photo again, and have to agree with you.

[newriverspey]

a lot of my flies have a tups look to them and they are my most productive flies. i don't know why but the trout certainly do like them where i fish. when the sulphurs aren't hatching, purple seems to work best for me. maybe later i will post a picture of the purple fly.

[DNicolson]

That is a very nicely dressed fly, a good recipe as well.
The Tup's fly was a West Country fly and this fly also reminds me of the Half Stone also a West Country fly.
http://donaldnicolson.webplus.net/page112.html
and here is the article on the Tup's Indispensible including Leisenring's Tup's Nymph.
http://donaldnicolson.webplus.net/page191.html

In the West Country they were not too fussy whether the flies were fished dry or wet.
With a cock hackle this would be a very nice Devon style fly.