308 DE. J. W. GREGORY ON THE PALEONTOLOGY [Aug. 1 895,. 



VII. Summary of Conclusions. 

 A. Correlation of the Barbados Sequence. 



Raised Coral Eeefs. Low Level 1 f Pleistocene. 



High Level/ [Pliocene. 

 Oceanic Series. Miocene (and possibly partly Plio- 



cene and partly Oligocene). 

 Scotland Beds, Oligocene (probably Lower). 



B. History of the Caribbean Area in Kainozoic Times. 



1. In Eocene times the site of the Windward Islands was a land- 



area. There is no adequate evidence of the existence of this 

 land in post-Tongrian (that is, post- Lower Oligocene) times. 



2. North and South America were then separated by a waterway 



across the Isthmus of Darien, and probably also across much 

 of the States of Costa Pica and Nicaragua. 



3. In early Miocene, or possibly Oligocene, times the two oceans 



were separated by the final emergence of Central America and 

 its union with a continuous land-area. 



4. There is no evidence, afforded either by stratigraphy or zoology,. 



to show that the Atlantic and Pacific Oceans have been united 

 across Central America in post-Miocene times. 



5. Approximative^ simultaneous with the rise of the west of the 



Caribbean Sea, subsidence was taking place to the east. This 

 plunged part of the area, now occupied by land, into abyssal 

 depths. True deep-sea oozes were then deposited in Barbados, 

 Trinidad, and Cuba. 



6. In some part of the late Miocene or Pliocene epoch re-elevation 



began. Deposits characteristic of shallower conditions (the 

 Archceopneustes a&rwpto-limestones) were formed : these con- 

 tain simple corals which, though too imperfect for description,- 

 indicate a depth of between 100 and 300 fathoms. 



7. In Pliocene or early Pleistocene times (probably the former) the 



continued elevation of the Barbados area brought it within the 

 zone of reef-coral growths. The first reefs formed were the 

 High-level Beefs, now raised nearly 1000 feet above the sea. 

 From these a continuous series forms a cap to the island, and 

 extends down to reefs of late Pleistocene age at sea-level. 



Synonymy of Corals. 



1. The types of the numerous species founded by Duchassaing & 



Michelotti have been examined. Thirty-three are now placed, 

 as synonyms. 



2. The following species, described as being from the West Indian 



Miocene, are reduced to the rank of synonyms. They have 

 been founded on Pleistocene specimens, probably included by 

 accident among: the Miocene fossils : — 



