THE ISLAND OF CUBA 41 



period. 1 The Organos are covered with a growth of pine 

 [Pirms cubensis) and flanked on either side by many beau- 

 tiful slopes and valleys, those on the south constituting 

 the famous Vuelta Abajo tobacco-lands. 



While the Sierra de los Organos proper cease just west 

 of Havana, the strike of their uplift, accompanied by the 

 same character of dark-colored protrusions of igneous 

 rocks flanked by the white Tertiary limestones, although 

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

 disconnected hills, in a gently curved line passing through- 

 out the central 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 intensity 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 bodv 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 Havana, Matanzas, Santa 

 Clara, and Puerto Principe are as follows: Almost due 



1 The general geology of the island, while not discussed in this book, is well 

 shown in many of the illustrations. It may be briefly stated as consisting of 

 an older basement of pre-Tertiary sedimentary rocks, in which Cretaceous and 

 probably Jurassic fossils have been found. Above this there are, first, littoral 

 beds composed of terrigenous material, and then a great thickness of white 

 limestones consisting of organically derived oceanic material, as distinguished 

 from true reef rock of late Eocene and Oligoeene age. Tin- island was re- 

 claimed from the sea and assumed its present relief by a great mountain-mak- 

 ing movement in late Tertiary time, succeeding the deposition of these lime- 

 stones. In later epochs, Pliocene and Pleistocene, the island underwent a 

 series of epeirogenic subsidences and elevations which affected the coastal 

 borders, producing the wave-cut cliffs and a margin of elevated reef rock 

 which borders the coasl in many places, as can be recognized in the illustra- 

 tions of the cities of Havana and Baracoa. So far as its history is known, the 

 island has never been connected with the American mainland, although BUCh 

 has frequently been asserted to be the ease. These assertions have been 

 based upon the erroneous identification <f certain vertebrate animal remains. 

 There arc no traces in the animal life oi Cuba, past or present, which justify 

 this conclusion. Some of the crystalline rocks may be very ancient, but mos1 

 of them are mid-Tertiary in age. 



