i?. Schofnburgk^ Dr. PhiL 87 
any one of these circumstances, or all connected, unfold and 
bring forth a change in the vegetation. 
A special characteristic of this region is the splendor of 
the flowers and the color of the representatives. Many 
species of plants found in other regions disappear here, and 
others appear, viz. : — Cinchoneae^ Proteaceae, Ternstroemieae, 
Ericeae, Vellosieae, gigantic Terrestrial Orchids, and tree 
ferns. The forests are less extensive, and do not attain the 
gigantic growth of the primitive forest, but are remark- 
able for their thick coriacious glossy foliage. They mostly 
extend along the valleys, generally only up to the middle of 
the mountains. The other parts of the mountains are wood- 
less, but covered with grass, on which appears, in groups 
and singly, a great variety of beautiful flowering shrubs and 
herbaceous plants. The grasses which cover the hills and 
table-lands are distinguished from those of the savanna, not 
only by their fresh green, but also by their more tender 
leaves. 
As rain is always falling in this region, there are no 
changes in the growth of the vegetation. 
Region of the Savanna. 
The central table-land or great savanna of British Guiana 
between and 62'^ of west longitude, is bounded in a northerly 
direction by the treeless Pacaraima Mountains, 4° north lati- 
tude ; southerly by the Carawaimi Mountains, and 3° 40' north 
latitude ; easterly by the forest region. The whole area of the 
savanna, in an absolute altitude of 350 to 400 feet above the 
level of the sea, may amount to 14,400 miles. 
The region of the savanna is also well watered. The main 
rivers are the Rio Branco, Takutu, Rupununi, Mahu, Zuruma, 
and Cotinga. The smaller creeks of the savanna are 
generally waterless during the dry season. In their main 
character the savannas of British Guiana differ from the 
Llanos and Pampas of the southern parts of South America; in 
the former the monotonous plains do not exist, the area which 
rises undulating, and here and there broken by groups of 
hills of isolated granite rocks, often 500 or 600 feet high — 
mighty blocks of conglomerate of oxide of iron, reddish 
colored masses of quartz and clay, which appear partly 
in single hardened fragments, but also in large blocks, 
cover in certain localities the surface. The heights of 
the undulating ground are generally covered with small 
