AGASSIZ: BAHAMAS. 113 



According to Mr. Dall, who has been kind enough to examine these 

 fossils, they " are of old Miocene age, the same as the age of Bovvdeu 

 in Jamaica and those of the Isthmus of Panama. They are also repre- 

 sented in Florida by what has been called the Chipola epoch, to which 

 the beds of Ballast Point, Tampa Bay, belong. Some of them appear 

 identical with fossils from the Chipola River, Florida. Fossils of the 

 same age were obtained on the Cuban coast by Professor R. T. Hill and 

 Dr. J. W. Spencer at various points." 



After passing the summit and descending to a point a hundred 

 and sixty feet above the level of the sea, we came upon a cut in the 

 road, where we found hard limestone and a small isolated head of a 

 fine Astraea, but no coral rock. From there down, the rock is hard 

 limestone greatly honeycombed, as are all the faces of the terraces 

 along the coast parallel to which the railroad runs. The first terrace, 

 upon which the railroad runs, is about twenty feet above the level of 

 the sea. It is nowhere more than three hundred feet wide, and forms an 

 ideal railroad bed. At Saboney the road enters into a gap of the shore 

 hills and soon passes out of the region of the limestone shore hills to 

 meet the dioritic rocks which compose the second range of mountains. 

 At tlie gap of Saboney, and thence to the westward, the second and third 

 terraces are very prominent. The second terrace is about fifty feet above 

 the first, and the third not more than sixty feet above that. The third 

 terrace is often obliterated by erosion. The first terrace in spots has 

 been carried away by the sea, and cliffs have been formed which reach 

 the height of the second or even of the third terrace. 



We were indebted to the courtesy of Mr. Shuman, the agent of the 

 Juragua mines, for an excellent opportunity to examine a part of this ele- 

 vated coral reef, forming the surface of the first terrace at Saboney, — 

 the old surface of the shore reef. We made good collections of speci- 

 mens of Mteandrin?e, two species of Astrajans, a large Colpophyllia, and 

 a fine Allopora, all belonging to species now found living.^ The corals 

 were clustered very closely, much as they would now be found growing 

 on a living coral reef, and quite as thickly packed. 



The examination of the terraces along the line of the Juragua Railroad 

 shows plainly that the vertical distance between the second and third 



1 The species of corals characteristic of the elevated reef (the " soboruco") be- 

 long to tlie following genera : Colpophyllia, Orbicella, Poritcs, Maeandrina, Agaricia, 

 Favia, Stephanoccpnia, Manicina, Madrepora, Isophyllia, and Siderastrea ; wherever 

 tlius far collected in the Caribbean, they all belong to recent species of reef builders 

 characteristic of the West Indian fauna. 



VOL. XXVI. — NO. 1. 8 



