ClipArt ETC
"A case in the form of a book in which to keep fishing-flies. It has leaves of Bristol-board or other stiff material. At the ends of the leaf are small hooks or loops to which the fish-hooks are attached so that the flies may be carried without bending the gut." -Whitney, 1911

Fly Book for Fishing

"A case in the form of a book in which to keep fishing-flies. It has leaves of Bristol-board or other…