If those were big (like size 12 big) I'm thinking some sub genus of the March Brown. I never went too far into the full identification thing, but when we had flies like that in a size 12 I knew them as the March Brown. When they were the same size but with the darker body and wing they were known as the Grey Fox.
They where almost a 12, Usually the Hendrickson hatch has come and gone by now (two weeks or so) and I thought the march browns where darker? It could be that I've got the two mixed up, I never could keep my bugs straight.
Boy, I don't know Tim............the size sounds about right and I've seen them in various tone of color. At any rate, rather than worry over the species I would be dubbing up some body's about that color and winging them with light bronze mallard flank.
That's what I do Ard, I was never very good at figuring out what type of bug it really was, especially not by the Latin name. I would just open my fly box and see what I had that looked close to what I saw, if there wasn't anything there, then I would tie some up before the next trip. Failing that, I used and adams or an EHC.