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AFRICA 



Senegambia is a low tract of land of a decided savana 

 type, while retaining a number of semi-desert plant 

 forms. South of the Gambia, the vegetation increases 

 in variety and luxuriance as it approaches the high- 

 forest region; yet the intervening sandstone plateaus 

 offer but stunted forms of woods and scrub, in which 

 acacias are predominant. Farther east, to the south of 





FIG. 81. High Savana Brush Nigeria. 



the Niger, the high tablelands are mantled with tall 

 grass interspersed with bushes, among which is the 

 landolphia rubber-bush. Trees are comparatively rare 

 and scattered, so that an open tree-steppe is formed : 

 towards the south, they fail entirely. In the plateau, 

 rivers have cut deep and narrow valleys the slopes of 

 which are forest-clad. 



