THK PLANT ECOLOGY OP DRAKENSBKRG BANGE. 513; 



gradual. On the borders of Basutoland it reaches its highest 

 altitude^ the Mont aux Sources being given on the maps as 

 11, 170; ft. (3405 m.), Cathkin Peak (Champagne Castle) as 

 10,357 ft. (3157 m.), and Giant's Castle as 9657 ft. (2944 m.), 

 but probably tliese heights are exaggerated. The general 

 altitude reached, by this part of the range may be taken as 

 approximately 3000 m. At the point where Basutoland 

 joins Griqu^land E., the main range bends south-westward,, 

 but a lower range passes along the boundai'y between. 

 Griqualand E. and Natal, terminating in the Ingeli 

 Mountains. 



• ., From the Mont aux Sources northwards along the boundary 

 of .the Free State, the altitude gradually decreases to Vaix 

 Reenen's Pass, this portion forming a range nearly at right 

 angles to the higher part, which continues in line to form the 

 boundary between Basutoland and the Orange Free State. 



From Van Reenen the portion bordering Natal rises again 

 slightly and forms a long escarpment facing Newcastle, which 

 has an altitude of 6500 to 7500 ft. (1981 to 2286 m.). 



This northern portion is much more accessible than the part 

 bordering Basutoland. 



The geology of the Drakensberg is fairly simple, owing to 

 the absence of folding. The rocks lie mors or less horizontally 

 and may be clas.sified in descending order as follows : 



'Amygdaloidal, basaltic, and rhyolitic 



lavas. 

 Cave Sandstones. 

 .Red Beds. 

 ^Molteno Beds. 

 Beaufort Series. 



Ecca Series (not including the glacial 

 conglomerate). 



The amygdaloidal lavas in some parts form practically 

 sheer cliffs, but there are numerous buttress-slopes covered 

 with a shallow layer of soil, in which tussock veld is formed, 

 and in places this reaches almost to the top even of the 



Upper Karroo 



Lower Karroo 



