GENERAL 199 



first on Madagascar, and the irregular mountains that 

 skirt the eastern tableland ; and by part of the mon- 

 soons being deflected and drawn towards the lofty mass 

 of Abyssinia. As a consequence, the mountain and hill- 

 ranges strewn over the high plains alone have sufficient 

 moisture for the maintenance of heavy rain-forests, and 

 these are so high that they are mountain forests rather 

 than selvas. The undulating high plain has a savana 

 climate and vegetation. 



The elevation of the Congo basin and the barriers 

 surrounding it reduce the rainfall, and thus the area 

 of the selvas, which are neither so widespread nor so 

 strongly developed as those of the Amazoni. South of 

 them the savana covers nearly the whole breadth of austral 

 Africa. The tropical type of grass-lands passes with 

 higher latitudes into a subtropical, then to a temperate 

 type. The bulk of the grass area corresponds to the 

 trade-winds belt on the oceans, and with the elevated 

 austral plateau on land. The sea winds spend their 

 moisture on the eastern and southern scarps of the 

 plateau, which are in consequence covered with a girdle 

 of forests. The tableland has only a moderate rainfall, 

 and the evaporation is greater. 



Mediterranean Africa. The Atlas Ranges separate 

 from Africa a strip of mountainous land, whose climate 

 is closely related to that of central and eastern Spain. 

 Mediterranean Africa or Mauretania, as it was formerly 

 called, extends from Tunis to Mogador, and it includes 

 a long and winding valley called the Tell hemmed in 

 between a lower and much broken coastal range and the 

 northern slopes of the Atlas. This broadens in the ex- 

 treme west into fertile plains open to the Atlantic 

 winds. On the whole, the country is fertile, and the 

 vegetation resembles that of the mediterranean portion 



