1897-98]. LATE FORMATIONS AND GREAT CHANGES OF LEVEL IN JAMAICA. 333 



the " White Limestone Formation " was Miocene. In the few cases, 

 where they gave Hsts of fossils in the local descriptions, their catalogues 

 have been considered by Dr. W. H. Dall to represent the lower 

 Miocene epoch, or what he now calls American equivalent of the 

 Oligocene beds, which occur in Florida and the Southern States. So 

 also in the list of fossils by Mr. Etheridge, he identifies the same forma- 

 tion, but unfortunately the localities were not given. Again, Mr, 

 Charles T. Simpson collected at Bowden, near Port Morant, in the 

 marly beds (probably in the lower part of the series at that locality), 

 about 500 species which Dr. Dall has only partly studied, yet, suffi- 

 ciently to pronounce them as belonging to what has been usually 

 called Lower Miocene or Oligocene. At that locality the fossiliferous 

 marl bed is only about a foot and a-half thick. 



East of the Turtle Crawl Harbour, a few miles from Port Antonic 

 Mr. Eugene Baker collected a quantity of fossils, and of the same 

 species the writer collected more specimens near the base of the great 

 limestone series. The fossils are entirely in casts, but of these Dr. Dall 

 has determined the following genera, and pronounces them as appar- 

 ently of Eocene age : — 



Xenophora. Velates. 



Turritella. Conus. 



Strombus. Natica. 



AmpuUina. Spondylus. 



Turbinella. Terebellum, two species. 



Both the Eocene and (old) Miocene fossils occur in the succession of 

 limestones forming a physical unit. The older Miocene is extensively 

 developed in Santo Domingo as shown by Dr. W. M. Gabb.* In the 

 Windward group, where the rocks have been particularly exposed to 

 erosion, Mr. P. T. Clevef found fossiliferous Eocene beds at the surface. 



From personal studies in Jamaica, Cuba and the Southern States, 

 and from all the information obtainable from other sources, the 

 writer is led to the conclusion that the great denudation of the West 

 Indies and the adjacent regions commenced rather late in the Miocene 

 period and did not culminate until in the Pliocene period, for over a 

 very wide region the same long continued erosion leaves only the 

 older Miocene without any remnants of newer Miocene or older 

 Pliocene or even Mid-Pliocene beds. This same absence of Mio- 



*" On the Topography and Geology of Santo nomiiig-o," by Wilh'am IM. Gabb, Trans. Am. Phil. Soc. 

 vol. XV., pp. 49-259, 1872. 



t" Outline of the Geology of North- Western India Islands," by P. T. Cleve ; Annals, N.Y., .Vcad. Sc. 

 vol. ii., pp. 185-194, 1882. 



