114 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



terraces, not being more than fifty to sixty feet, is not of greater height 

 than the depth at which corals would readily grow up from a new base. 

 The flat surface which forms the upper part of the elevated reef, the first 

 terrace, is covered with several species of corals apparently killed in situ 

 by the gradual elevation of the base upon which they were growing, and 

 of which they formed the living top at the time the elevation began. 

 The lower portions of the reef have grown up at greater depths, and, 

 as they died or were covered by more flourishing or by growing corals, 

 have formed the base upon which the newer crop built their way little 

 by little to the surface. The terraces as we see them form a series of 

 steps, each of considerable width, so that the fifth terrace, for instance, 

 might be fully twelve to fifteen hundred feet horizontally removed from 

 the shore line. Of course the first terrace may have been much wider 

 than where I measured it, and much of its sea face may have been worn 

 away. Still, as the depth off the south shore of Cuba is very great, and 

 the limit of coral reef builders is at almost every point of the coast 

 reached within a comparatively short distance, it is not probable that 

 the width of the first terrace was very considerable. The examination 

 which I made does not settle the question that each of the terraces cor- 

 responds to a separate growth of corals laterally ; it neither proves or 

 disproves the former continuity of the coral reef, nor its division through 

 the agency of the waves into perhaps one or more distinct terraces. I 

 can only say that tlie character of the rock exposed on the faces of the 

 second and third terraces showed quite plainly that they consisted of 

 older rocks with very marked differences, — differences which would in- 

 dicate a greater age in the face of the second terrace than in the first, 

 and a still greater age in the third, but not necessarily, as the terraces 

 niav have been cut successivelv in limestone of the same age. The con- 

 dition of the fossil corals was specially marked, and the differences 

 noted in fossilization quite agreed with the different conditions of the 

 limestones of the second and third terraces as contrasted with each 

 other, or as compared with that of the first and youngest elevated coral 

 reef terrace. We may conclude that at Saboney at least tlie fii-st ter- 

 race only is composed of an elevated coral reef, while the limestones 

 of the second and third terraces are much older, and, although containing 

 a few corals, yet are not coral i-eef limestones. 



It may be that the isolated corals identical in species with those now 

 living or with those of the elevated reef forming the first terrace, which 

 are found on the second and third terraces near Santiago, at Baracoa, and 

 to' heights of nearly five hundred feet near Banes, are the remnants of 



