LIFE IN THE DESERT. 69 



of hard, thorny shrubs are scattered over the dreary waste, 

 the chief of which is the Hedysarum of the Sahara, a 

 plant about eighteen inches high, which is green through- 

 out the year ; it grows absolutely out of the arid sand, 

 and is eagerly cropped by the camels of the caravans. 

 There are also beetles, which burrow in the sand ; and 

 nimble lizards which shine, as they bask in the burning 

 sun, like burnished brass, and bury themselves on being 

 alarmed. The lizards probably live upon the beetles; 

 but what the beetles live upon is not so clear. 



The enormous plains of South Africa, called karroos, 

 though not so absolutely barren wastes as the Sahara, are 

 still great wildernesses of sand, exposed to periodical 

 droughts of long duration. These regions are occupied 

 by a most singular type of vegetation ; fleshy, distorted, 

 shapeless, and often leafless, tribes of euphorbias, stapelias, 

 mesembryanthemums, crassulas, aloes, and similar succulent 

 plants, maintain their hold of the sandy soil by the weak 

 support of a single wiry root, and are fed rather by the 

 dews of heaven than by the moisture of the soil. During 

 the rainless months of the dry seasons, these plains are 

 scarcely less arid than the sandy deserts of the north ; 

 yet even then there are reservoirs beneath the surface. 

 Livingstone speaks of a certain plant, named leroshua, 

 which is a blessing to the inhabitants of this desert. 

 " We see a small plant with linear leaves, and a stalk not 

 thicker than a crow's quill ; on digging down a foot or 

 eighteen inches beneath, we come to a tuber, often as 

 large as the head of a young child ; when the rind is 



