PREFACE. 
— 
Tue 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 
Apocynacee, 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 1868, 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. Urrer Gurnea.—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. Nie Lanp—A. F. Broun, a collection of plants from the 
M. T. Dawe, a collection of plants from Uganda. W.G. 
s from Uganda. Sir H. H. Johnston, a 
a. J. Mahon, a collection of plants 
llection of plants from the Blue and 
ollection of plants from South 
a collection of plants from 
Soudan. 
Doggett, a collection of plant 
collection of plants from Ugand 
from Uganda. C. E. Muriel, a co 
White Nile. Captain M. 8. Wellby, a ¢ 
Abyssinia and Lake Rudolph. A. Whyte, 
Uganda and British East Africa. 
IV. Lower Guivea.—J. Gossweiler, plants from Angola. H. Hua, 
