SE Sa 
     
    
   
     
  
  
  
  
  
  
  
  
  
   
    
  
    
   
   
     
   
    
the entire region. 
Soil appears to be the dominating influence in forming the topographic 
characteristics which have been listed. Only the more pronounced features are 
outlined in the illustrations. The entire terrain is a repetition of those indicat- 
ed features appearing in less pronounced appearance plus other features enum- 
erated. 
The steep flutings, vertical valleys or chutes found in the ravine walls of 
the uplands have been considered as due to the effects of solution as observed 
in basaltic and limestone regions under a tropical Climate. 
Numerous hot springs, lack of detritus throughout the entire region and 
the scarcity of surface flow in the uplands in contrast to the amount appearing 
on the coastal plains indicate that surface flow is nota predominating factor in 
forming topography. 
The theory here presented is of the nature of a first hypothesis. With no 
erosion process accounting for the listed features, the mentioned theory ap- 
pears, at present, to be the logical conclusion. 
NOTES 
l/ Although the vegetation in the eastern Venezuela illustration is not typi- 
cally savanna, the area is classified as semiarid by Peveril Meigs in 
maps prepared for the Ankara Symposium on Arid Zone Hydrology (1953). 
Vegetation indicates a more humid climate than that of the grassy sa- 
vannas. 
2/ Soil, the yearbook of Agriculture 1957 U.S. Dept. Agriculture 
U.S. Government Printing Office Washington, D. C. 
i 
The Columbia Lippincott Gazetteer of the World 
Columbia University Press New York, 1952 
> 
"Australian physiographers (apparently unique in this regard) have for 
long recognized that the depth of ready erosion (upon rejuvination of ter- 
rain) may be governed by the presence of unweathered hard rock beneath 
the oxidized zone."