Epiphytes (plants which grow on other plants, not parasitically but for support), comprise more than one-third of the total vascular flora in some tropical forests. Growing within tropical forest canopies, epiphytes are subject to severe environmental constraints, and their diverse adaptations make them a rich resource for studies of water balance, nutrition, reproduction and evolution. This book synthesizes the body of information from research on epiphytes and their relations with other tropical biota, and provides a comprehensive overview of basic functions, life history, evolution, and the place of epiphytes in complex tropical communities. Tropical ecologists and zoologists as well as plant scientists will find this volume a useful guide to research on the twenty-five thousand species of epiphytes which root in the crowns of tropical trees.