XIII. 

 ON THE SEA-SHORE. 



THE coast of Guiana is made up of the alluvion 

 brought down by the great rivers in past ages, 

 which by the continual work of trees and sedges 

 and grasses has been raised to the surface of the 

 water, so that it can now be brought under cultiva- 

 tion. The original coast line once coincided with 

 the sand-reefs, which are at present at an average 

 distance of about twenty miles from the shore all 

 between them and the ocean is the result of floods 

 and vegetation. It has generally been supposed 

 that this deposit is entirely due to floods, but that 

 such is by no means entirely the case we shall 

 endeavour to show. As in the forest, along the 

 banks of the rivers and in the swamp, plants have 

 had a great deal to do with the result as we see it, 

 and are still working quietly but continually for the 

 same ends. 



As certain trees have been developed to contend 



with the flood, so others are fitted for the struggle 



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