ANTIQUITY OF THE VOLCANOES 269 



composed entirely of organic material, which with several other islets 

 stands above a shallow submerged platform extending out from the 

 southeast end of Grande Terre and Basse Terre. Grande Terre was un- 

 doubtedly once a volcanic pile like Guadeloupe. It was planed down 

 to sealevel by the waves, covered with shells, and reelevated to its present 

 position, all of which processes required time. 



To the southward of Grande Terre is the island of Marie Galante, of 

 the same topographic and geologic type. This archipelago exhibits a 

 long battle between the processes of volcanic pile-up, marine degrada- 

 tion, elevation, and subsistence since the original vulcanism began. 



In Saint Christopher, Saint Eustatius, Guadeloupe, Martinique, Saint 

 Lucia, and Grenada patches of disturbed fossiliferous beds of Pleistocene 

 or recent age are occasionally found interbedded in volcanic debris on 

 the lower seaward slopes at altitudes of 200 to 900 feet above the sea, 

 showing that vulcanism existed in or prior to Pleistocene time, and that 

 the volcanic piles themselves participated in the regional uplifts, else- 

 where described. The fossils enumerated are hardly older than Pliocene, 

 and are most probably Pleistocene, and their position around the edges 

 of the piles show that the great mass of the islands were ejected in 

 previous epochs. 



In general it may be stated that with the exception of Cuba the oldest 

 and nucleal rocks proven in the Great Antilles and Windward islands 

 are volcanic ejecta similar in material to that of the present ejecta, and 

 that with the exception of Barbados * all the accompanying sedimentary 

 rocks are either the local sediments derived from these old volcanoes or 

 from the remains of oceanic animal life which lived on their slopes. 



More direct and scientific proof of the antiquity of these volcanoes is 

 found in the record of the fossils of the sedimentary rocks here and there 

 veneering the volcanic piles or interbedded with them. The calcareous 

 and sedimentary formations of the Windward islands are all Tertiary, 

 Pleistocene, and recent age.f 



HOW THE OCEAN TEARS AWAY AS THE VOLCANOES BUILD UP 



The intelligent traveler sailing down the islands may see, if he knows 



* The basement series of this island, as I have elsewhere shown, is South American in its affini- 

 ties and unlike the Windward islands, 

 t These may be divided into three distinct age categories : 



1. Older beds represented in the northern islands of Saint Bartholomew, Antigua, and possibly 

 Saint Martins and Saint Christopher, containing fossils which may be temporarily referred to the 

 Eocene. 



2. Marly formations found in Antigua, Saint Croix, Grande Terre, Guadeloupe, and possibly 

 Barbados, which have been referred to the Oligocene. 



3. Indurated calcareous muds, marls, and shell debris and true reef rock of an age so recent that 

 they cannot be paleontologically differentiated, but probably include the Pliocene, Pleistocene, 

 and recent period. 



