Acknowledgements: We are thankful to the Directors/ Curators of the following herbaria for herbarium and library facilities and for sending the specimens on loan: BM, BSD, E, G, K, KUH, LE, LINN, LIV, MIR, RAW, UPS, W and WU. We gratefully acknowledge the financial support from Russian Foundation for Basic Research (05-04-48669) provided to I. G. Levichev and financial support for this publication from the Andrew Mellon Foundation and National Science Foundation (DEB0103783), Washington, U.S.A., obtained through the Missouri Botanical Garden, St. Louis, USA. We are grateful to Professor Peter H. Raven of the Missouri Botanical Garden for his assistance in securing the support. We are extremely obliged to Stella Ross Craig and Joanne Langhorne for kindly permitting us to republish some of their illustrations.We are thankful to J. Edmondson, S. Ghazanfar, A. Haigh, D. Harris, C. Jarvis, R. Kamelin, L. Klimes, Brian Mathew, D. Nicholson, H. J. Noltie, S. Owens, A. Smith, J.-M. Tison and E. Vitek, for their kind help from time to time. Thanks are also due to N.N. Nadel for correction of Latin text and E. Bidois for partial correction of English text. Grateful thanks are due to Professor Pirzada Qasim Raza Siddiqui, Vice-Chancellor, University of Karachi and Professor Zafar Iqbal, Chairman, Department of Botany, University of Karachi for providing working facilities to the project and for their understanding and encouragement.