162 OUTLINE OF PLANT GEOGRAPHY 



ebony, the latter related to our persimmon. Among the notable 

 trees are species of silk-cotton (Ceiba, Bombax), trees of the largest 

 size, with enormous buttresses supporting the huge trunks. Other 

 trees belong to the nutmeg family (Myristicaceae), and the 

 Euphorbiaceae have numerous representatives. 



Some of the t rees exceed 200 feet in height, and among them are 

 species with showy flowers, which, however, are quite invisible to 

 the wanderer in the forest floor beneath. Among the best known 

 of these is Spathodea campanulata, related to our Catalpa and 

 trumpet creeper, whose big orange-scarlet bell-shaped flowers are 

 very handsome. This tree is quite common in cultivation through- 

 out the tropics. 



Where the light is sufficient there is a heavy undergrowth of 

 herbaceous plants. Some of the Araceae, and Scitamineae (gingers, 

 Cannas, bananas, etc.) are especially conspicuous and the ponds 

 and shallow river margins show a profusion of aquatics: sedges, 

 water-lilies, pond-weeds, etc. Some of the climbing Araceae are 

 very conspicuous, as they are in nearly all wet tropical regions. 



The Scitamineae include several species of true bananas (Musa), 

 distributed over tropical Africa, in addition to the many cultivated 

 varieties of plantains and bananas. The gingers (Zingiber, Costus, 

 etc.), are extremely abundant in the wet districts, and Canna 

 indica is a common weed, as it is in many countries w r here it has 

 been introduced from America. 



Of the sedges, the famous papyrus (Cyperus Papyrus) is abun- 

 dant in many other parts- of tropical Africa, as well as in the Nile 

 district. 



Compared with the equatorial regions of America and Indo- 

 Malaya, the West African forest flora is relatively limited in 

 extent and poor in species, especially in such very characteristic 

 types as the palms and orchids, both of which attain their max- 

 imum development in the American and eastern tropics. This 

 is true also of the Araceae. 



A remarkable result of the more recent studies in the flora of 

 equatorial West Africa is the demonstration of unmistakable 

 relationships with tropical America. Engler * gives a long list 

 of genera and species peculiar to West Africa and America, or 

 predominant in these regions. Examples of these are the two 



1 Loc. cit, pp. 984-980. 



