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INDEX TO THE STKATIGEAPHY OF NORTH AMERICA. 



These four series of rocks are unconformable to one another and are the products of the 

 greater events in the geologic history of the island. • 



Hill gives a tabular summary of the geologic history of the island, of which the 

 following is a part : 



Geologic formations on Jamaica. 



In his table Hill placed the line between the late Cretaceous and early Eocene 

 above the Richmond. In copying the table it has been moved to a position below 

 the Richmond, on recommendation of T. W. Vaughan and in accordance with the 

 text of Hill's work, which shows clearly that he regarded the Richmond as early 

 Eocene. 



The late Cretaceous rocks of Jamaica are called Blue Mountain series, of which 

 Hill says : 



This series comprises the oldest rocks of the island. It consists of loose or slightly, indurated 

 beds of gravel, clay, bowlders, and tuffs, with exceptional beds or bosses of hard indurated 



