1. Department of Botany, University of Wisconsin, 430 Lincoln Drive, Madison, Wisconsin 53706;
2. Harvard University Herbaria, 22 Divinity Avenue, Cambridge, Massachusetts 02138;
3. Molecular Systematics Section, Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3DS, UK
4. De Paul University, Department of Biological Sciences, 2330 W. Kenmore Avenue, Chicago, Illinois 60614