1 CUBA AND POKTO ItICO 



Mountain region. South America is the eastern continent, 

 and terminates with the end of the northern Andes in the 

 Republic of ( Jolombia. The Central American continent is 

 an east-and-west isthmus connecting the termini of the 

 North and South American continents. Central America 

 and the West Indies, including the Gulf of Mexico and the 

 Caribbean Sea (together forming the American Mediterra- 

 nean), are more complex features, largely individual in their 

 aspects, although more nearly related to one another and 

 to the northern coast of South America than they are to 

 the main bodies of the larger continents. 



Geography has taught that the American continents are 

 dominated by a continuous CordiMeran system running like 

 a backbone through South, Central, and North America, 

 connecting the whole western border of the hemisphere by 

 one great mountain system, which has persisted through 

 long epochs of time. This is an erroneous idea, for the so- 

 called continental backbone is not a geographic unit, but 

 is disconnected in places. In a later chapter I will show 

 that the Central American isthmian barrier between the 

 oceans was once freely invaded by the waters of the Pacific, 

 while an entirely different isthmian bridge on the windward 

 or eastern side of the Gulf and Caribbean Sea, now partially 

 destroyed, probably connected or almost connected the 

 continents from Florida, to the northeast point of South 

 America. Either this, or much of the present Central 

 American lands, with some of the West Indian Islands, 

 long before man appeared on this earth, formed a great 

 archipelago a veritable Atlantis extending east and west 

 between and directly across the trends of the North and 

 South American continents. 



The east-front ranges of the North American Cordilleras 

 are largely composed of old sediments of the Atlantic Ocean 

 which were pushed up against a preexisting land lying to 

 the west ; they are mountain ranges with north-and-south 

 trends, accompanied by volcanic intrusions and ejecta. 

 Geographers show that this system abruptly terminates 



