228 AFRICA 



a few masses of higher plateaus, the vegetation of which 

 differs in many respects from that of the surrounding 

 lands. The Futa-Jallon has already been briefly men- 

 tioned. Other highlands occur in Togo, in a general 

 north and south direction. North and east of the 

 Cameroon the extensive tablelands of Adamawa and 

 Ngaundere separate the interior basin of the Chad from 

 the basin of the Gulf of Guinea, and possibly continue 

 between the Gaboon and the Congo basins. Here rivers 

 flow at the bottom of narrow gorges which harbour 

 dense and luxuriant forests of the selva type. The 

 hills and plateaus, on the other hand, display a dry kind 

 of vegetation, contrasting with the exuberance of the 

 Cameroon and Gaboon. There seems to be a recurrence 

 of the flora of drier lands, with the acacias and other 

 plants of the Sudan : mixed brush- woods of middle-sized 

 deciduous trees alternate with grass stretches in a park 

 landscape : forests of Combretaceae display in January 

 a fresh pale and shimmering verdure; palms are rare, 

 epiphytes and climbers both scanty and small. The 

 drier character of these plateaus is possibly due to the 

 more complete drainage, and to the winds. Similarly, 

 the little known hill- and plateau-land which forms the 

 watersheds between the Shari, Ubanghi, and Bahr-al- 

 Ghazal basins, appears to have a vegetation different 

 from that of the valleys, composed of light woods and 

 park-lands, in which the baobab and the borassus palm 

 fail. The trees are small or of moderate size, and 

 include amongst others the butter- and tallow-tree, 

 numerous members of the acacia and mimosa tribes, and 

 many other shrub forms with small leaves. 



The plateaus to the north and east of the Cameroon 

 are, to a large extent, under prosperous native cultivation. 



The Congo Basin ' is a circular plain-like basin, some 



