1. Department of Environmental Biology, State University of New York, College of Environmental Science and Forestry, Syracuse, New York 13210; Email: (TWH) ; and (DJS) djstewart@esf.edu. Send reprint requests to DJS.
2. Departamento de Biología, Facultad de Ciencias, Escuela Politécnica Nacional, Ladrón de Guevara E11-253 Quito, Ecuador; Email: .
3. 5755 Nutting Hall, Room 234, University of Maine, Orono, Maine 04469-5775; Email: .