538 



toises ; those of the Serra do Espinhap (chain 

 of Villarica), 950 toises ; those of Serra do los 

 Vertentes (groupe of Canastra and the Brazilian 

 Pyrenees) 450 toises. Further west, the sur- 

 face of the soil seems to present but slight un- 

 dulations ; but no measure of height has been 

 made beyond the meridian of Villaboa. Con- 

 sidering the system of the mountains of Brazil 

 in their real limits (as we have indicated 

 above), we find, except some conglomerates, 

 the same absence of secondary formations with 

 which we were struck in the system of the 

 mountains of the Oroonoko (groupe of Parime). 

 These secondary formations, which rise to con- 

 siderable heights in the Cordillera of Venezuela 

 and Cumana, belong to the low regions only of 

 Brazil i, 



B. Plains (Llanos) or Basins. 



We have now successively examined, in that 

 part of South America situated on the east of 

 the Andes, three systems of mountains, those of 

 the shore of Venezuela, Parime, and Brazil; 

 we have seen that this mountainous region, 

 which equals the Cordillera of the Andes, not 

 in mass, but in area and horizontal section of 

 surface, is three times less elevated, much 

 poorer in precious metals adhering to the rock, 



* Eschwege, p. 15. 



