FLORA OF EAST AND MIDDLE AFRICA 51 



appears with the Hypericum and the tree heaths in groves 

 on the lower edge of the zone. 



The upper half of the moorland zone is given a weird 

 appearance by the prevalence of forests of tree groundsels, 

 Senecio keniensis. This plant exhibits a striking variety 

 of form ranging from a globular mass of large radical leaves, 

 in appearance like a cabbage, in youth, through a thick- 

 stemmed, barrel-shaped plant a few feet in height, and 

 finally to a tall woody-stemmed, branching tree capped by 

 immense club-shaped heads of dense leaves. Straggling 

 forests of groundsel occur from twelve thousand feet to near 

 the snow-line, but at the upper level they gradually dwindle 

 in numbers and size, and those which reach the snow are 

 only a few small, radical-leaved forms. Groundsels of sev- 

 eral species are found throughout the world as common 

 roadside weeds, but nowhere except in the highlands of 

 Africa do they exhibit such large tree forms. 



Associated with the groundsels are two species of lobelia. 

 Lobelia gregoriana of the middle altitudes and a tall, woolly 

 pubescent form. Lobelia telekii, which is abundant in the 

 tree groundsel forest and continues up to snow-line. Both 

 of these are peculiar in form and quite far removed from 

 the lobelias of our gardens. 



Throughout this upper alpine zone the Alchemilla is 

 lacking, its place being taken by the heavy tussocks of a 

 grass-like rush, Ucinia, which covers the hummocky, boggy 

 soil to the snow-line, where it alone carries on the struggle 

 with the cold. Growing everywhere over the whole moor- 

 land are found the daisy-like white and pink flowers of 

 Heliochrysum in clumps and isolated patches. 



The alpine vegetation of equatorial Africa is distinct 



