Contents

28 September 1984
Vol 225, Issue 4669

About The Cover

Demosponge (Halichondria panicea) encrusting an intertidal surge channel in Torch Bay, Alaska. Sponge morphology varies in a sophisticated way with wave action. In changing environments, sponges begin production of wave-tolerant tissues more quickly than wave-intolerant tissues. This reduces the risk of catastrophic tissue loss in an unpredictable environment. See page 1478. [S. R. Palumbi, Department of Zoology, University of Washington, Seattle 98195]