History of the Island of Cuba. 211 



That some of these rivers do at present reach tide level a 

 short distance from the beach is true, but so short is this dis- 

 tance that vessels can always obtain fresh water from them by 

 sending light boats up them less than a mile from where they 

 enter the seas or harbors. 1 do not think that this slight in- 

 dentation of tide level up these rivers is indicative of " drown- 

 ing " or an ancient subsidence ; on the contrary, it merely 

 means that the rivers and surf are doing their normal work of 

 degrading the land. If there were really drowned rivers they 

 would be navigable some distance inland, but in case of the 

 three largest streams, the Armendaris of Havana and the 

 two Tumuris of Matanzas and Baracoa I found it impossi- 

 ble to go inland over a mile in the shallowest row boat, being 

 soon retarded by rapids. 



On the other hand some of these streams are now forming- 

 delta deposits in places outside their mouths, which is more 

 indicative of present elevation than of subsidence. Further- 

 more, the Yumuri of the east formed similar deltas before the 

 elevation of the coast reef. At any rate, if there had been 

 any serious epochs of subsidence, they would be recorded in 

 great fiord-like valleys or low passages across the central axis 

 of the Island, such as do not exist, and to which the oval 

 harbors may not be compared, for their origin is entirely due 

 to the pre-existing fringe reefs. 



On the other hand, it might be alleged that all the ancient 

 topography of subsidence is still beneath the ocean level, and 

 that the angular edges of Cuba are indicative of the fact that 

 the present outline merely represents an ancient summit which 

 is re-emerging. The submarine topography, however, is not 

 within the province of this paper, but I agree with Prof. 

 Agassiz that its irregularities were indicated long before the 

 present history treated, in this paper. The three alternations 

 of gravel and reef in the Matanzas section may also have indi- 

 cated slight alternations of subsidence and elevation. 



It is now possible with the aid of the stratigraphic and pale- 

 ontologic data previously given to make a few conclusions con- 

 cerning the Cenozoic history of Cuba. It has been shown by 

 the stratigraphy that the topographic levels are not old reef 

 levels but with the exception of the modern reef, have all 

 been carved out of the previously folded and disturbed Ter- 

 tiary limestones, and hence the present bench topography of 

 Cuba originated subsequently to this period of Post-Tertiary 

 wrinkling and represents a different kind of movement which 

 was regional or epeirogenic. Since the old folding or orogenic 

 movements occupied at least a small portion of Post-Tertiary 

 time, we may reasonably conclude that the periods of uniform 



Am. Jour. Sci.— Third Series, Vol. XLVIII, No. 285.— Sept., 1894. 

 14 



