6i8 



ZONES AND REGIONS [Pt. Ill, Sect. II 



a caricature. At first, trees still occur in close woods ; the short trunk of each, as 

 thick as one's body, bears a green crown of branches, which are as thick as one's finger, 

 quite leafless, partly pendant and partly interlaced. The plant is Euphorbia Tirucalli, 

 certainly wild in this locality, whilst along the coast, and also in Abyssinia, it appears 

 to be introduced. Further in there are only a few little trees entangled with Cissus 

 quadrangularis, common everywhere, or with C. rotundifolia ; they are Acacia, Salva- 

 dora, a species of Gymnosporia (Celastraceae) with its leaves pointing to the zenith, 

 and Anaphrenium abyssinicum (Anacardiaceae). Here, on the other hand, the sandy 

 plain for miles, as far as one can see, is covered with plants from two to six feet in 

 height, which form very distinct individual groups, separated from one another by soil 

 that is either bare or covered by the acanthaceous thorny herb Blepharis Togodelia. 

 Each group consists mainly of the thorny cactus-like euphorbias— 'Euphorbia heteroc- 

 proma and an undescribed species with long-thorned, trigonous, broadlj'-fluted 



Fig. 354. Trans-Caspian desert, Kara-bugaz. Saline soil. From a photograph by Andrussow. 



members' — but intermingled with them are distributed the other proletarians, as 

 I have called them, of the plant kingdom, which, if possible, appear more rough and 

 ragged than the euphorbias. Caralluma codonoides (Asclepiadaceae) sends up tetra- 

 gonous, thorny shoots as thick as one's arm, bearing at their extremities balls, as large 

 as a child's head, of stinking, almost black flowers; next to it a species of Adenium 

 (Apocynaceae) with a gnarled stem, branches like a Sarcocaulon, and narrow lanceo- 

 late leaves, expands its brilliant, fragrant, stellate flowers ; a species of Kleinia is 

 taller than either with its white, leafless system of juicy branches. We also find the 

 three species of Sansevieria (S. cylindrica, S. Ehrenbergii, S. Volkensii), and a fourth 

 broad-leaved species, although they are not prominent here when compared with the 

 succulent plants. Blanks are filled by the yellow-flowered Talinum caffrum (Por- 

 tulaceae), which everywhere occupies the worst and driest soil ; occasionally by 

 a species of Stapelia with coral-like thorny branches prostrate on the sand, and 

 brown marbled flowers over a couple of inches across. The strangest forms, how- 

 ever, that we see here and there occupying the centre of a group of plants, are 

 immense tubers about one meter broad and nearly as high, resembling round blocks, 

 some of which appear smooth as if covered with light-coloured leather, others 

 roughly granular and dark green. They belong to two species of plants, among the 



