OF THE LLASOS. 367 



Llanos of the Lower Orinoco, the Meta, and the 



Guaviare ............................................................ 29,000 



Plains of the Amazon ............................................ 260,400 



Pampas of Rio de la Plata, and Patagonia ............ 135,200 



Plains between the eastern chain of the Andes 



of Cundinamarca and the chain of Choco ........ 12,300 



Plains of the shore, on the west of the Andes .... 20,000 



456.900 



The whole surface of South America contains 571,300 

 square leagues (20 to a degree), and the proportion of the 

 mountainous country to the region of the plains is as 1 to 

 3'9. The latter region, on the east of the Andes, comprises 

 more than 424,600 square leagues, half of which consists of 

 savannahs ; that is to say, it is covered with gramina. 



SECTION II. 



General Partition of ground Direction and inclination of the strata- 

 Relative height of the formations above the level of the Ocean. 



IN the preceding section we have examined the inequalities 

 of the surface of the soil, that is to say, the general structure 

 of the mountains, and the form of the basins rising between 

 those variously grouped mountains. These mountains are 

 sometimes longitudinal, running in narrow bands or chains, 

 similar to the veins that preserve their directions at great 

 distances, as the Andes, the littoral chain of Venezuela, the 

 Serra do Mar of Brazil, and the Alleghanies of the United 

 States. Sometimes they are in masses with irregular forms, 

 in which upheavings seem to have taken place as on a laby- 

 rinth of crevices or a heap of veins, as for example in the 

 Sierra Parime and the Serra dos Vertentes. These modes of 

 formation are linked with a geognostic hypothesis, which has 

 at least the recommendation of being founded on facts ob- 

 served in remote times, and which strongly characterize the 

 chains and groups of mountains. Considerations on the 

 aspect of a country are independent of those which indicate 

 the nature of the soil, the heterogeneity of matter, the super- 

 position of rocks, and the direction and inclination of strata. 



