MUSEUM OF COMPARATIVE ZOOLOGY. 275 



Comparison and Correlation of Various Levels. 



Let us now compare the various data presented concerning the coast 

 and inhmd topography at the various localities mentioned, and inquire 

 into their relation to each other. Figure 8 of Plate I. will aid in under- 

 standing the presentation to follow. 



That the soboruco or elevated reef represents the same general level 

 around the north and south coasts of Cuba is indisputable, and can be 

 interpreted in no other way than that there has been in recent time a 

 uniform elevation throughout the nine hundred miles represented in the 

 length of the island. It is the same formation topographically and geo- 

 logically, wherever seen, and establishes the fact that the elevation of 

 the island, at least during one epoch, was general, and not local or spas- 

 modic. If such a uniform movement has beyond doubt taken place at 

 a modern epoch, it establishes the principle that similar elevations were 

 not impossible in the past. 



The levels represented in the three terraces of the Yumuri of the east 

 have remarkable identity with the levels of the west end of the island, 

 as at Havana and Matanzas, where my detailed studies were made. The 

 only ditference is, that the latter are wider than the former, owing to 

 the lower and more rounded character of the country out of which they 

 were cut. The correspondence in altitude is such that no one can doubt 

 that they represent synchronous and identical regional movements and 

 pausations, and that they were once continuous throughout the length 

 of the north coasts of the island, and around Cape Maysi to the Santiago 

 coast. 



The Cuchilla, or dissected peneplain of the east, presents a remarkable 

 analogy to the higher dissected summits back of Matanzas, constituting 

 the upland divide of the west end of the island in the latitude of Havana. 

 Hei-e the old levels represented by these summits are less distinct than 

 in the east, probably owing to the fact that this end of the island had 

 not previously been so highly elevated as the east. 



The oldest and highest limestone summits, appi'oximating from fifteen 

 hundred to two thousand feet, as typified in Yunque, the Sierra del 

 Moa, the Pan de Matanzas, the table land of Mariel, and the Managua 

 Paps of the west half of the island which follow near the north coast, the 

 highest limestone at Santiago and other places, represent the remnant 

 of the oldest and highest level or levels, which have been so completely 

 dissected and planed down that their extent can only be estimated. 



