Vili PREFACE. 
Hooker, under the authority of the Home or of Colonial Governments 
it is necessarily uniform in general plan with those which have been 
already issued. 
“The principal features of this plan, as settled by Sir W. J. 
Hooker, and described in his report, are these :— 
“ Ist. The descriptions are drawn up in the English language, 
Mr. Bentham’s ‘ Introduction to Botany, drawn up with special reference 
to Local Floras,’ containing the technical terms used in the descriptions, 
being prefixed to the work. 
“2nd. The general sequence of Natural Orders adopted is that of 
the ‘ Prodromus’ of De Candolle, being that which experience has 
shown to be practically the most convenient. In accordance with this 
sequence, British Botanists are accustomed to arrange their Herbaria 
and works of descriptive Botany. In the more detailed arrangement 
of the genera, the ‘Genera Plantarum’ of Messrs. Bentham and 
Hooker has been followed, and a reference to that work is given with 
each genus. 
“With regard to the synonymy of the species here described, while 
the authors have endeavoured to quote all names which have been 
applied to Tropical African plants, they have not, in the case of widely 
diffused species, regarded it as either necessary or desirable to include 
their whole synonymy, the reliable citation of which would have 
involved very much more time, labour, and space than the end to be 
attained would warrant; besides that, it would be out of place in a 
special work of this kind. Any new identifications of African with 
extra-African species are, of course, recorded.” 
In one particular, however, I have been obliged to depart slightly 
from the plan of my predecessor. The last of the three published 
volumes of the “ Flora of Tropical Africa” appeared in 1877. Since 
then our knowledge of the vegetation has increased very greatly. 
Large tracts which were unexplored botanically at that date have 
yielded numerous and copious collections. In resuming the work, it 
has therefore been found necessary to more clearly define the regions 
into which Professor Oliver divided the whole area. In attempting 
this, advantage has been taken as far as possible of political boundaries, 
since they admit of easy recognition. The regions may now be briefly 
defined as follows: 
1. Upper Guinga.—The Western Coast region from the mouth 
of the Senegal River to the southern boundary of the Cameroons. It 
contains practically the whole of the Niger Basin. It is bounded 
on the north by a line stretching from the mouth of the Senegal 
River to Lake Chad; on the east by the 15th meridian of East 
longitude to its intersection with the southern boundary of the 
Cameroons, which bounds it to the south. It includes also the island 
of Fernando Po. 
2. Norta Crentrat.—This includes the Sahara. It is bounded to 
the north by the Tropic of Cancer; on the west by the Atlantic; on the 
east by the 26th meridian of East longitude ; on the south by the Upper 
Guinea region and the Congo Free State. 
