The Fly Fishing Reporter has provided an excellent resource for all trout chasers: a very enjoyable video, available via Ralph and Lisa Cutter, that gives nice views of the various types of mayflies. Here is the the link to the FF Reporter (Ken Sperry) and a cool visual. Linked twice just in case. Add FF Reporter to your blog roll.

http://www.foxvalleytu.org/html/mayfly_larvae.html