HILL : GEOLOGY OF JAMAICA. 67 



great White Limestone Series, concluded that, " this being so, it is 

 clear that the overlying White Limestone Series cannot be older than 

 early Pliocene." ^ 



The trnth is, the white limestones of the Jamaican sequence represent 

 several distinct formations and ages, from Vicksburg to recent inclu- 

 sive, but that the greater portion of it, as I shall show, is of old Oligo- 

 cene acre. There are even some white limestones in the Cretaceous in 

 Clarendon which are almost lithologically indistinguishable from those 

 of the Tertiary. In recent years English geologists have observed the 

 discrepancies of previous interpretations of the white limestone, and 

 suggested, from specimens of the material sent them, that at least an 

 upper and lower division might be distinguished.^ Our investigations 

 will show that not two but several subdivisions can be made, and that 

 the rocks hitherto classified under this general head really belong to 

 several distinct formations of two great series, the Oceanic and the 

 Coastal, the former constituting most of the rocks of this character and 

 occupying large areas of the interior upland, while the latter are con- 

 fined to a narrow belt along the coast. 



The older white limestone formations, constituting the greater mass 

 of these rocks, are found in the upland area of the island, and are all 

 of Tertiary age. More exactly speaking, they are of the Vicksburg 

 stage, which is placed in the Eocene by some writers and in the Oligo- 

 cene by others. The later white limestone formations — including the 

 Coast Limestone of the Jamaican Reports, which we shall describe as 

 the Falmouth Formation, and the Hospital Point Limestone of Montego 

 Bay — are of Pliocene, Pleistocene, and recent age. 



There has also been much vagueness concerning the origin of these 

 rocks, accompanied by an opinion on the part of many that they are of 

 coral reef origin. They have been described ^ as " great coral structures, 

 from the debris of which the enormous calcareous development of the 

 White limestone has been derived," and as the " great coralline struc- 

 ture which covers the greater part of the island." * Opinions of this 

 nature have caused some writers to believe that all the white limestones 

 were of coral reef origin, and led to the rather careless assertion that 

 reef rocks of great thickness occur in the Antilles at heights exceeding 

 2,000 feet, when in fact such rocks nowhere except in Barbados exceed 

 100 feet in altitude or thickness. On the other hand, even the local 

 descriptions of the Jamaican Reports controvert the conclusion that 



1 Quart. Jour. Geol. Soc. London, 1892, Vol. -XLVIIL p. 220. 2 jbid., p. 219. 

 8 Jamaican Reports, p. 24. 4 Ibid., p. 189. 



