The Madam X in yellow is an awesome fly to have in your terrestrial box. As far as dry flies that can twitch in the water go, this is perhaps the best. They are easy to see and will float great throughout your drift. When you approach a river and see hoppers, stoneflies, and caddis, go ahead and tie on a Madam X in yellow. It’s a universal trout fly that is considered the best of its kind by many guides and anglers alike. A few different sizes are key, the small ones are the most effective and stealthy. While the larger ones make the best splash and catch the biggest fish.