Try this fly just on dark for the evening dry fly action. 

What does it imitate - This is a good imitation of an emerging midge insect. Midges will often be the first thing to start hatching as dark approaches well before caddis start. Make the most of these early rises by matching the midge hatch.

 How to fish -When you first start to see rises coming up to dark. Cast ahead of rising fish and try to get a natural drift.

Why is it successful - It imitates a midge that is heading for the surface.