PREFACE. 



The large and constantly increasing mass of material has exceeded the 

 space allotted to it, and has made it necessary to divide the present 

 volume of the " Flora of Tropical Africa" into two sections. 



The concluding part of the present section has been delayed as far 

 as practicable in order to include in the Addenda the most recent 

 additions to our knowledge of the Orders described, and especially to 

 bring up to date what has been ascertained with regard to the 

 Apocynacece^ which include most of the caoutchouc-producing plants of 

 Tropical Africa, as well as others yielding medicinal products of great 

 value. 



For the amended definition of the regions into which the area of 

 the flora is divided, reference may be made to the preface to the 

 seventh volume. 



In the prefaces to the first, fifth, seventh, and eighth volumes, will 

 be found an enumeration of the materials employed up to 18G8, and of 

 the most important additions to them which have reached Kew since. 



The further collections at Kew cited in the present volume are : 

 I. Upper Guinea. — T. B. Dawodu, plants from Lagos. Geheimrath 

 Dr. A. Engler, a collection of Warnecke's plants from Togo. L. Kentish- 

 Rankin, plants from Northern Nigeria. D. Sim, a collection from 

 Liberia. A. Whyte, a collection from Liberia. 



III. Nile Land — A. F. Broun, a collection of plants from the 

 Soudan. M. T. Dawe, a collection of plants from Uganda. W. G. 

 Doggett, a collection of plants from Uganda. Sir H. H. Johnston, a 

 collection of plants from Uganda. J. Mahon, a collection of plants 

 from Uganda. C. E. Muriel, a collection of plants from the Blue and 

 White Nile. Captain M. S. Wellby, a collection of plants from South 

 Abyssinia and Lake Rudolph. A. Whyte, a collection of plants from 

 Uganda and British East Africa. 



IV. Lower Guinea. — J. Gossweiler, plants from Angola H. Hua, 



