364 ZONES AND REGIONS [Pt. Ill, Sect. I 



same, at least in plains (Figs. 127 and 195). Tali grasses, in many districts 

 exceeding the height of a man, spring up in dense tufts, separated bj' bare 

 intervals of soil, which is very variable, ph}-sicall\^ as well as chemically, 

 and is frequenth' coloured red b,\' iron oxide. On high plateaux the 

 grass is shorter, frequently not taller than in our meadows, and more 

 intermingled with herbaceous perennials and under-shrubs At greater 

 or less distances apart trees appear, usually as stunted, gnarled, dwarf 

 trees, resembling our apple-trees, but occasionally as lofty individuals, 

 which as a rule belong to characteristic species not present in the forest. 

 Besides dicotyledonous trees palms also occur in savannah. 



When the trees become closer, the savannah passes over into savannah- 

 forest, and when the trees disappear it passes into steppe. Such transitions 

 are frequent, and are sometimes occasioned by climatic causes, but more 

 frequently by changes in the nature of the soil. 



ii. SA VANNAH IN AFRICA. 



Pechuel-Losche has given a vivid description of the savannah on the 

 Loango coast, which may be considered as generally typical of the 

 physiognomy of savannah in lowlands. However, the baobab (Adansonia 

 digitata) is not in the picture, nor are the thick-leaved dwarf trees which 

 rise singly above the grass and which the author describes elsewhere 

 (Fig. 196). He distinguishes two forms of savannah, the open and closed 

 savannah. Open savaniiali ' consists of less fully packed, and more loosely 

 distributed flexible grasses, less than a man's height, which allow of one's 

 passing through them and of having a sufficient view of the surroundings ; 

 the c/osed savannah consists of densely crowded stiff grasses, which shoot 

 vigorously upwards, and which act as a strong barrier to the natives and 

 render any digression from the trodden path either very difficult or 

 impossible. . . . The open grassland occupies the greater area. The main 

 part of it consists of grasses about one meter high. In many districts, 

 scattered all about among these there are, gracefully waving in the breeze, 

 very loose sprays of a charming Andropogon and Cymbopogon, three 

 meters in height, and of a shorter Ctenium. The closed grassland, even 

 when it has become transformed into stunted jungle, is almost entirely 

 formed of Paniceae, the stiff culms of which spring up four and five meters 

 high. The latter height is however already relatively considerable and 

 exceptional, and according to numerous measurements a length of five 

 and a half meters is to be considered as the extreme limit of growth. 



'The vegetative activity of all campine^ glasses occurs during the 

 season when storms are rife ; before this season is over, the grasses have 

 matured their seeds and begin to die, like the wheat in our [Central 

 European] fields. Even during their most rapid development they never 



' Canipinc = savannah. 



