This book is what it sounds like, a superb new major reference on the mayflies that keep fly fishermen impassioned and insane. It goes on the shelf alongside Fred Arbona's 1980 Mayflies, the Angler, and the Trout, Al Caucci and Bob Nastasi's 1985 Hatches II and Gary LaFontaine's 1990 The Dry Fly: New Angles, to mention only the most recent lineage. Knopp and Cormier offer a detailed analysis of the major species and subspecies at all life stages, tailoring the presentation to what anglers need to know about fly design and presentation. Mayflies is an indispensable, beautifully produced reference work.
-- Gray's Sporting Journal