NATURE -- Still time to make the Washington Butterfly Association monthly meetng, 6 p.m., at the Downtown Public Library Branch, Room 1A, 906 W. Main St in Spokane.

Presentation is by Brook Swanson, a Gonzaga University riologist, on "The Evolution of Arthropod Weapons." a fast-paced, entertaining review of current research and field study from one of a group of northwest area experts in this fascinating field of study.