296 DR. J. W. GREGORY ON THE PALEONTOLOGY [Aug. 1895, 



represented in the collection. There is moreover a Lithophyllia 

 cubensis (M.-Ed. & H.) ; it is said to be derived from some recent 

 raised reefs, but the exact locality is not stated. 



These two collections conclusively prove that the Antigua series 

 of cherts and limestones are neither Pleistocene nor Pliocene, as 

 has recently been suggested. They are certainly either Oligocene 

 or Miocene — probably the former. 



VI. The Correlation op the Barbados Eocks and its Bearing 

 on the History of the Caribbean Area. 



The Barbados Sequence. — The island of Barbados is composed of 

 a series of rocks which may be classified as follows : — 



Eaised Coral Eeefs. { Low-level Reefs. 



Oceanic Series. { ^faopneustes abruptus-Limestone. 



I Thalassic Marls. 

 Scotland Beds. 



That these occur in the above sequence there can be now no 

 doubt, thanks to the labours of Messrs. Jukes-Browne and Harrison * 

 and Col. H. W. Peilden 2 ; but in the first geological map and de- 

 scription of the island, 3 the rocks now known as the Oceanic Series 

 were said to overlie the coral-limestones, while Schomburgk 4 de- 

 scribed the deep-sea marls as interstratified with the Scotland Beds. 



The Age of the Coral-Limestones. — The Low-level Beefs yield a rich 

 molluscan fauna (see Part III. of this paper), which proves that these 

 are of late Pleistocene age. The determination of the date of the 

 other divisions of the sequence is a difficult task. Let us in the first 

 place consider the correlation of the High-level Beefs. These are 

 stratigraphically continuous with those of the lower levels, and it 

 might at first sight appear unnecessary to separate them. There 

 are, however, distinct differences in the fauna. Of the 31 species 

 of corals found in the raised reefs of Barbados, 4 species and 3 genera 

 are not known to occur at the present time in the West Indian seas. 

 Nine of the recent species are recorded from the Nivaje Shale of San 

 Domingo, which is assigned by Gabb 3 to the Middle Miocene. This 

 would therefore appear to suggest that the corals have so long a 



1 J. B. Harrison and A. J. Jukes-Browne, ' The Geology of Barbados, being 

 an Explanation of the Geological Map,' etc. (1890), 8vo. 64 pp. and map ; also 

 ' The Geology of Barbados. — Part I. The Coral-Rocks of Barbados and other 

 West Indian Islands,' Quart. Journ. Geol. Soc. vol. xlvii. (1891) pp. 197- 

 250, and ' Pt. II. The Oceanic Deposits,' ibid. vol. xlviii. (1892) pp. 170- 

 226. 



2 H. W. Feilden, ' On the Birds of Barbados,' Ibis, ser. 6, vol. i. (1889) 

 pp. 478^79. 



3 Jas. Dutt. Maycock, 'Flora Barbadensis .... to which is prefixed a 

 Geological Description of the Island,' London, 1830, pp. 15-17, pis. L, ii. 



4 R. H. Schomburgk, ' The History of Barbados,' 1847, pp. 546-557. 



5 W. M. Gabb, ' On the Topography and Geology of Santo Domingo,' 

 Trans. Amer. Phil. Soc. new ser. vol. xv. (1881) pp. 88, 101. This author, 

 however, includes in the Miocene deposits which yield a smaller proportion of 

 extinct species than usually occurs in that system. 



