Griffith’s Gnat This post was last updated on May 12th, 2014 at 12:40 amGriffith’s Gnat Is a very simple fly to tie. It only has two required materials, peacock herl and hackle. This is a good general pattern that will work when there are smaller flies on the water. The hackle sort of looks like flapping wings of a gnat, black fly or even a midge. I have had this simple pattern pick up some very large trout that I could not get to hit a much more complex looking fly. This is a great fly to have on hand, because it looks like such a wide array of different insects all in one simple little package.