138 



The Hydrosere. This Jitters even less than the xerosere- 

 from the midland Veld of Natal. The chief difference lies 

 in the relative greater abundance of certain species, especially 

 Imperata arundinacea, Ischaemum fasciculatum var. arcuatum, 

 Rottboellia compressa var. fasciculata, Panicum interruptum, 

 Leptocarydion vulpiastrum, Diplachne fusca, Stenotaphrum 

 glabrum, Trichopteryx dregeana, Eragrostis namaquensis, 

 though most of the other hygrophilous sjjecies occur. Phrag- 

 mites communis lines the rivers for long distances. In Zulu- 

 land Cyperus madagascarensis, the Zululand Papyrus, is of 

 considerable importance. 



As a climax type, the Barringtonia consociation, which, 

 occurs in wet sandy soils, is of interest. 



The Halosebe. The early stages have Salicornia and 

 Chenolea diffusa, the climax Mangroves, Avicennia officinalis, 

 Bruguiera gymnorhiza, and Rhizophora mucronata. This 

 occurs at the river mouths on the mud flats, and grasses hardly 

 enter into it, except sometimes Sporobolus pungens, but it 

 is difficult to draw any hard and fast line between the halo- 

 sere and the psammosere as the soil water in the latter is 

 sometimes brackish, sometimes not. The psammosere also 

 merges into the hydrosere, since the sand is usually not dry, 

 but on the contrary rather moist. As a rule the climax stages 

 of the psammosere are more mesophytic than the initial stages,, 

 but not always. 



MOUNTAIN TUSSOCK GRASSVELD. 



This very distinct type of grassland occurs on the slopes 

 of the Drakensberg, at altitudes of 4,000-8,000 feet, extending 

 all the way round to the Stormberg, and it is also character- 

 istic uf other foothill ranges in Natal and the Eastern Cape 

 Colony. The grasses grow in densely caespitose tufts as a 

 rule, and they are rather xerophytic forms with setaceous or 

 sub-setaceous or firmly folded or convolute leaves. The old 

 leaf bases persist forming dense stools or tussocks, which 

 collect the usually red soil, and stand up a few inches above 

 the level of the rest of the ground. There are very narrow 

 bare spaces between the tussocks. 



While there is sometimes a certain amount of mixing 

 with Anthistiria-Andropogon Veld species, the 'Tussock Veld 

 is on the whole very distinct in its composition also. Aristida 

 is rather poorly represented, but A. bipartita, A. angustata, 



