FLORA OF EAST AND MIDDLE AFRICA 39 



Afzelia cuanzensis, and species of Comhretum and Albizziay 

 which are mixed with an undergrowth of scrubs alHed to 

 Acanthus. Much of the tropical coast zone is covered by 

 scattered bush and grassy areas, interspersed with soHtary 

 trees of Acacia stenocarpa, Bauhinia reticulata^ Erythrina 

 tomentosa, baobabs, and occasional doum-palms and cande- 

 labra euphorbias. 



Succeeding the tropical coast belt we find the desert 

 nyika zone stretching far inland as a dry, thorn-bush- 

 covered steppe. The nyika covers the greater part of the 

 region of east equatorial Africa and in it are found most of 

 the floral and faunal peculiarities of East Africa. All of 

 the country lying between the altitudes of five hundred 

 and three thousand feet are comprised in it. The Uganda 

 Railway traverses the zone from the station of Mazeras to 

 Makindu, a distance of one hundred and sixty miles actually, 

 but by the railroad some two hundred miles. Northward 

 .the nyika broadens out tremendously, attaining in the 

 region north of Mount Kenia a width of over four hun- 

 dred miles, and extending unbroken from the seashore 

 inland past Lake Rudolf to the Nile. The region is quite 

 level, with a gentle slope to the coast, and occasional 

 isolated hills or small mountains of gneiss rising a few 

 thousand feet above the plain. A heavy, bright-red clay 

 soil covers the region universally, except where the gneiss 

 rocks project above it. 



The nyika is subject to a long, dry season during which 

 most of the trees and bushes are leafless and the soil is 

 bare. The vegetation is on this account fitted In every 

 possible way to resist evaporation and is typically xerophytic. 

 During the short rainy season, which is irregularly dis- 



