THE PLANT ECOLOGY OF THE COAST BELT OF NATAI-. -387 



a wide distribution, and the coi*responding plant coninmnities 

 differ but little witli considei^able climatic variations. The 

 Cyperaceas and other marsh and water plants include a 

 great many species that extend through the tropics, but the 

 same species also extend through the rest of Natal with 

 a few exceptions. In the same way, many of the strand 

 plants have a wide distribution and extend through the 

 tropics not only of Africa but of Asia as well — and even 

 South America. Rnderal species growing in constantly 

 disturbed habitats are distinctly tropical on the whole, but 

 these are mixed with many that ai-e just as distinctly 

 temperate and range all over South AfricM. 



In the main xerosere the vegetation becomes distinctly 

 more and more tropical in its physiognomy and floristic 

 composition as succession advances. The enrliest stages 

 include species belonging to the Crassulaceaj, Aizoace^ 

 (e.g. Limeum viscosum), Selaginella rupestris and 

 several others, which represent a type much more charac- 

 teristic of the midlands of Natal and other colder parts of 

 South Africa. Primitive grassveld dominated by species 

 of Aristida, Eragrostis, Sporobolus, etc., is practically 

 identical with the same type in the midlands. Even at a 

 further stage of the succession Anthistiria imberbis is 

 again dominant on the coast belt, as it is over most of the 

 rest of the soutli-eastern grassveld. In the numerous vernal 

 aspect socies so abundant in the grassveld the same affinity 

 with the corresponding midland types is seen. Bulbous 

 Monocotyledons, Compositas, Leg.uminosa?, Soro- 

 phulariacea3, etc., and a fair number of distinctly teu]- 

 perate species are common. It is interesting, too, to 

 compare the grassveld species of Asclepiadaceaj, which 

 all belong to genera much better represented in other parts 

 of South Africa, with the climbing species of the same family 

 found in the coast belt scrub and forest which are distinctly 

 tropical. 



As the climax stages of the succession are reached the 

 vegetation becomes much more tropical. Among the trees 



