VEGETATION IN THE DUNES 



face, yet the strong winds, the intense light 

 and great heat radiated from the white sand 

 approximate the conditions of a desert. Both 

 the desert cacti on the one hand and tlie sea 

 rocket and saltwort on the other conserve 

 moistm'e by making reservoirs for water in 

 their stems and leaves, taking on a fleshy 

 habit, in the language of the botanists. The 

 saltwort also resembles the cacti in its spiny 

 defenses. It always seemed to me a cruel 

 state of affairs that in the deserts, where vege- 

 tation is so scanty, the plants should be so 

 forbiddingly spine-covered; but after all Na- 

 ture always looks after the individual, she is 

 not altruistic. These sand dune plants are 

 then true xerophils,— lowers of dryness. 



In the same situation near the edge of the 

 beach grows the cockle-bur with its beaked 

 and spiny fruit, and also the salt-loving orach. 



In photographs of the semi-arid regions of 

 eastern Africa, one sees great spreading trees, 

 giant candelabra, xmder which the rhinoceros 

 takes his noonday siesta. These are euphor- 

 bias or spurges, and here throughout the 

 dunes a lowly member of the same family, 

 the seaside spurge, spreads itself in mats from 

 the size of a silver dollar to that of a large 



73 



