THE PALAEOTROPICS L63 



common mangroves, the wine-palm, and a species of oil-palm 

 (Elaeis), as well as many others. Engler concludes thai there must 



have been more or less complete land connections between South 

 America and Africa, at some earlier period. 



Much of the more elevated portions of tropical Africa is occupied 

 by grass-land and open forest or savanna, with a sub-tropical 

 rather than tropical climate. The grass flora is a very rich one and 

 is a very important constituent of the African vegetation, much 

 of the " veldt" in the Transvaal and Rhodesia looking quite like 

 the prairies of the western Mississippi valley and Great Plain-. 

 These grasses comprise many such wide-spread genera as Andro- 

 pogon, Panicum, Paspalum, Agrostis, etc., but tropical Africa pos- 

 sesses a considerable number of genera, either strictly endemic or 

 majnly African. Examples of these are Beckera, Perotis, Schmid- 

 tea, Chaetobromus. 1 



In addition to the numerous grasses of the open plains and 

 savannas, there are giant grasses like the common reed (Phragmites 

 vulgaris) and various bamboos; and the wild sugar cane (Sac- 

 charum spontaneum) is common in many places. A good many 

 grasses, like the bamboos and many smaller species, are found in 

 the wet forest, and such forest grasses usually have soft and rel- 

 atively broad leaves. 



Tropical East Africa 



The equatorial portion of the East coast offers a marked con- 

 trast to the opposite side of the continent. Nowhere, at sea-level, 

 is the rain-forest developed, and only back of the coast, at the base 

 of the mountains which intercept the rains which pass over the 

 immediate coast, is a rain-forest encountered. It is much less 

 luxuriant than the west coast forest both because of the limited 

 extent of the area of heavy precipitation, and because a large 

 part of the forest has been cleared for agriculture. 



As one sails along the East African coast the shore for the most 

 part shows a sandy beach. Mangrove swamps are found where 

 rivers discharge, as at Beira in Portuguese East Africa and other 

 points along the coast, and in places, back of the shore are hills 

 clothed w r ith forest; but the trees are mostly deciduous, and in 



Angler, loc. cit., p. 902. 



