22 
ZOOLOGICAL GEOGRAPHY. 
[part III. 
along the whole of which there is (almost certainly) one con- 
tinuous virgin forest. Its greatest extent from north to south, is 
from the mouths of the Orinooko to the eastern slopes of the 
Andes near La Paz in Bolivia and a little north of Sta, Cruz de 
la Sierra (lat. 18° S.), a distance of about 1,900 miles. Within this 
area of continuous forests, are included some open “ campos,” or 
patches of pasture lands, the most important being, — the Campos 
of the Upper Bio Branco on the northern boundary of Brazil ; a 
tract in the interior of British Guiana ; and another on the 
northern bank of the Amazon near its mouth, and extending 
some little distance on its south bank at Santarem, On the 
northern bank of the Orinooko are the Llanos, or flat open plains, 
partly flooded in the rainy season ; but much of the interior of 
Venezuela appears to be forest country. The forest again pre- 
vails from Panama to Maracaybo, and southwards in the Magda- 
lena valley ; and on all the western side of the Andes to about 
100 miles south of Guayaquil. On the N.E. coast of Brazil is a 
tract of open country, in some parts of which (as near Ceara) 
rain does not fall for years together ; but south of Cape St. 
Boque the coast-forests of Brazil commence, extending to lat. 
30° S., clothing all the valleys and hill sides as far inland as the 
higher mountain ranges, and even penetrating up the great valleys 
far into the interior. To the south-west the forest country re- 
appears in Paraguay, and extends in patches and partially 
wooded country, till it almost reaches the southern extension of 
the Amazonian forests. The interior of Brazil is thus in the 
position of a great island-plateau, rising out of, and surrounded 
by, a lowland region of ever-verdant forest. The Brazilian sub- 
region comprises all this forest-country and its included open 
tracts, and so far beyond it as there exists sufficient woody 
vegetation to support its peculiar forms of life. It thus ex- 
tends considerably beyond the tropic in Paraguay and south 
Brazil ; while the great desert of Chaco, extending from 25° to 
30° S,, lat. between the Parana and the Andes, as well as the high 
plateaus of the Andean range, with the strip of sandy desert on 
the Pacific coast as far as to about 5° of south latitude, belong to 
south temperate America, or the sub-region of the Andes. 
