HILL: GEOLOGY OF JAMAICA. 163 
These movements have collectively constituted the great oseillations 
Whereby, since the close of Cretaceous time, the land and sea bottom have 
Fieurr 39. Coast Benches, Trelawney. 
Moved up and down, resulting in the expansion or shrinking of the re- 
"espective areas in harmony with these movements. 
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Fraurn 40. — Changes of Level in the West Indian Region. 
These oscillations, as summarized upon the accompanying diagram, 
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