37* 



ZONES AND REGIONS 



[Pt. Ill, Sect. I 



Humboldt, have received other impressions of the llanos. The boundless 

 grassland that Humboldt described was not revealed to our eyes, but, on 

 the other hand, a park-like country, in which woodland forms oases and 

 strips in the grassland, and the grassland usually occurs in the guise, 

 not of treeless steppes, but of savannah scantily dotted with solitary trees 

 (Fig. 20c). 



A similar park-like appearance, a similar differentiation of the grassland 

 as savannah, according to Schomburgk's description 1 , belongs to the 

 savannah-districts of Guiana : — 



' Forests— I have termed them oases— sometimes miles across, sometimes of less 



Fig. 202. From the Brazilian campos of Minas Geraes. The small tree : Andira inermis (?). Left 

 hand : Bromelia bracteata. Also Eremanthus sphaerocephalus and Ipomoea sp. After Warming. 



extent, most frequently with a circular outline, rise out of the savannah, like islands 

 from the sea. . . . Fringing the rivers of the savannah for a width of usually 100 

 to 200 feet, but often more, is a band of vegetation, not luxuriant indeed, but 

 consisting of closely crowded trees and shrubs. . . . The "grass" of the savannah 

 consists for the most part of Cyperaceae with yellow, rough-haired, straggling 

 stems, and they are intermixed with a number of prickly, woody, and herbaceous 

 plants belonging to the families Malpighiaceae, Lcguminosae, Rubiaceae, Myrtaceae, 

 Malvaceae, Convolvulaceae, Menispermaceae, Apocynaceae, and others. Stunted 

 habit characterizes the growth of the trees, such as Curatella, Bowdichia, Psidium, 



1 Schomburgk, I, p. 798. 



