276 Plants and their Ways in South Africa 



3. The Karroo Region. — North of the vSouth-West region, and extending 

 somewhat further east, there is a similarly curved region with the Nieuwveld 

 mountains as a northern boundary. It is a large shallow basin surrounded 

 by mountains. Violent rains have carried off the soil. Grazing flocks, 

 by destroying vegetation and thereby loosening the soil, aid in the process, 

 and year by year the rivers have carried away "the dust of continents yet 

 to be." The climate is marked by dryness and extremes of heat and cold j 

 the desert of the dry season becomes a garden after rain. Its plants are 

 thorny and succulent, with underground storage systems. Acacia horrida 

 (Karroo thorn), Portulacaria afra (Spekboom) Sarcocaulon (Candlebush), 

 Testudinaria (Elephant's foot), serve as examples. 



4. The Upper Karroo, or Region of Compositae, a mountainous region 

 lying north of the Karroo region, but not extending to the Orange River 

 except at the extreme east and west, has a flora in some respects similar to 

 that of the Lower Karoo region, Init Composites abound, some of which 

 furnish excellent food for stock. 



5. The Kalahari Region is the name which Dr. Bolus gives to the 

 large tract of land lying to the north of the Composite Region, west of 

 the Natal Region and south of the Tropic of Capricorn. The western 

 coast strip is a weird desert producing the curious Welwitschia on stony 

 o-round among the sand dunes, and the Naras, or Acanthosicyos horrida. 

 The latter is one of the Calabas family. It has roots as large as a man's 

 arm and 50 feet or more in length. They push down until they find water 

 below the sand of the desert. The rigid green stems have opposite thorns 

 in the axils of reduced leaves. Growing in sandy places, the winds sweep 

 over and often completely bury the stems. The stems push quickly up, 

 and the sandhills are often built upon the plants, in the centre. A bitter 

 juice protects all parts but the sweet juicy fruits, which are eaten by jackals 

 and Hottentots. 



To the east and north the region is largely a grass country. The tufts 

 of grass grow to a great height. Between the months of November and 

 February large tracts of grass look like fields of corn. Maize reaches a 

 height of 8 to 13 feet, and it becomes necessary to cut down the stalks in 

 order to 2;et at the grain. 



