The CDC (Cul De Canard) feather has wonderful floating capabilities, one of its best uses is in the CDC buzzer. A deadly pattern wherever buzzers are hatching. Used on a floating line, the fly is cast out and then either wait for the trout to take the fly, cover a rise with the fly or pull the CDC under the surface of the water and allow it to resurface with the buoyancy of the CDC feathers, the latter method can have dramatic catching effects.
Wind the thread down the hook shank to a point part way around the hook bend, catching in some fine pearl mylar as you go.
Dub some the body fur onto the thread and create a nice tapered body up to a position around 1/3 of the hookshank from the eye.
Take the pearl mylar and using even spaced turns create a rib up to where the tapered body stops.
Catch in a bunch of CDC feathers with the ends towards the hook bend. (Feathers towards the hook eye). You will need to experiment with the length and number of feathers, this varies with each size and type of hook.
Dub some the body fur onto the thread and create a nice bushy thorax over the cdc ends.
Whip finish by securing the thread around the hook eye itself and not the CDC, this makes sure that the eye is clear of CDC feathers.
Pull the Hares Ear fibres out by using a dubbing puller or a piece of velcro. This creates a nice buggy effect.