208 JR. T. Hill — Tertiary and later 



reached by still higher mountains of the Sierra Maestra to the 

 southward. On every side the drainage has cut deep below 

 this peculiar mountain, carving the lovvlying country into an 

 intaglio of serrated hills. 



No one can view this or other similar summits without be- 

 ing impressed with the story they tell of the great erosion 

 which has taken place around them, as well as the fact that the 

 difference in elevation between its plateau and that of the 

 lower lying Cuchilla plain represents a vast hiatus in the his- 

 tory of the island's elevation — a long period during which 

 land stripping and degradation ensued, reducing the surround- 

 ing areas to the old Cuchilla erosion level. 



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 difference is that the 

 latter are wider than the former, owing to the lower and more 

 gently sloping 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 move- 

 ments and pauses, and that they were once continuous through- 

 out the length of the north coasts of the island and around 

 Cape Mayci to the Santiago coast.* 



The Cuchilla, peneplain of the east, presents a resemblance 

 to the higher summits back of Matanzas constituting the upland 

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



The oldest and highest limestone summits, about 1500 to 

 2000 feet in height, as typified in Junki, the Sierra del Moa, 

 the Pan de Matanzas, the table land of Mariel, and the Mana- 

 gua paps of the west half of the island which follow near the 

 north coast, the highest limestone of Santiago and other places, 

 represent the remnant of the oldest and highest limestone 

 levels which have been so dissected and planed down that, 

 their extent can only be estimated. These elevations collec- 

 tively may represent a higher land than existed before the 

 Cuchilla plains were developed. Whether the high summits 

 of the Sierra Maestra adjacent to the Santiago coast preserve 

 traces of still older and more ancient levels is an interesting 

 problem for the future. The interpretation of these levels 

 cannot be finally given, without more extensive study, but the 

 obvious history is as follows : 



(1) In a period near the close of the Tertiary to be ascer- 

 tained, previous to the emergence of the present elevated reef 

 and the erosion of the Cuchilla plain, there was a great upward 

 movement of the island to the height of at least 2000 feet, 



* The levels of the Santiago region are described by Kimball in this Journal of 

 Dec, 1884. 



