VI 11 PREFACE. 



H. Courtet, Dr. A. Engler, Dr. J. W. C. Goethart, Dr. J. A. Henriques, 

 Professor H. Lecomte, Dr. C. A. M. Lindman, Dr. C. H. Ostenfeld, 

 Professor R. Pirotta, Dr. A. B. Rendle, Professor Hans Schinz, Professor 

 E. Warming, Dr. R. Wettstein, Dr. E. De Wildeman, and Dr. A. 

 Zahlbruckner, for the generous loan of type specimens and other mate- 

 rial from the herbaria under their charge. 



I must add my final acknowledgments of the aid given me by 

 Assistants in the Herbarium of the Royal Botanic Gardens; to Mr. 

 0. H. Wright, A.L.S., in preparing the manuscript for the press and in 

 checking the proofs ; and to Mr. N. E. Brown, A.L.S., for working out 

 the geographical distribution. 



For the detailed topography the third edition of the " Spezial-Karte 

 von Africa" (Gotha : Justus Perthes, 1893) has been chiefly used. 



W. T. T-D. 



WiTCOMBE ; Fehmanj 17, 1913. 



I 



