202 CUBA 



Eocene age, intruded by ancient mid-Tertiary igneous rocks, the 

 debris of which makes a clay and gravel soil — one of the two 

 contrasting types which constitute the greatest wealth of the 

 island. 



The Sierra Maestra crest closely parallels the adjacent sea- 

 coast, toward which its slopes descend precipitously. Inland, 

 toward the north, the slope is gentler, the eroded ridges* leading 

 gradual^ down to the valley of the Cauto, the deep indentation 

 of which nearly separates these mountains from the region to the 

 north. The second group of mountains, the Sierra de los Or- 

 ganos, is found in the extreme western province of Pinar del Rio, 

 extending northeast and southwest between Mariel, near Habana, 

 and Cape San Antonio. This range consists of lower ridges of 

 geologic formation different from those of the Sierra' Maestra. 

 Its summits culminate in the Pan de Guajaibon, west of Habana, 

 which has an altitude of 2,532 feet. Its rocks are composed of 

 deformed sedimentaries of supposed Paleozoic, Triassic, Jurassic, 

 and Tertiary age, the uplift of which may have been cumulative, 

 but culminated during the close of the last-mentioned period. 

 The Organos are covered with a growth of pine and flanked on 

 either side by many beautiful slopes and valleys, those on the 

 south constituting the famous Vuelta Abajo tobacco lands. 



While the Sierra Organos proper cease just west of Habana, 

 the strike of their uplift, accompanied by the same character of 

 igneous protrusions flanked- by Tertiary limestones, although 

 void of the older rocks, is traceable by a series of low discon- 

 nected hills, in a gently curved line passing throughout the cen- 

 tral plain of the island and to the north of the third or central 

 group of Trinidad into the western part of the province of Puerto 

 Principe. Thus, in a manner, this line of uplift, varying in in- 

 tensity from the sharp ridges of the west to low flattened folds 

 in the middle provinces, constitutes the nearest resemblance to 

 an axial backbone of the body of the sinuous outline of the island, 

 while the Sierra Maestra constitutes the head. The principal 

 components of these interrupted summits of low relief dotting 

 the plains of Habana, Matanzas, Santa Clara, and Puerto Prin- 

 cipe are as follows: Almost due south of Habana, commencing 

 east of the village of Santiago, is a range of low, timbered hills, 

 surrounded by plains, including the Tetas de Managua, the Areas 

 de Canasi, Lomas de Camoa, the Escallera de Jaruco (which is 

 visible from a great distance), and the Pan de Matanzas. Along 

 the north coast between Habana and Matanzas there are many 



