198 BULLETIN: MUSEUM OF COMPARATIVE ZOÖLOGY. 
similar phenomena indicating harmony of elevation and submergence in 
previous epochs can be made out. The cut plains of the north half of 
Antigua and the Grande Terre of Guadeloupe elearly show that regional 
elevations have taken place after the close of Miocene time, followed 
by erosion epochs and a Pliocene or early Pleistocene subsidence some- 
what analogous to the Lafayette events. The bordering reefs formed on 
the rising platforms at Marie Galante and Desirade, and the double terrace 
structure of Barbuda show that these islands participated in the general 
Post-Pleistocene elevation of all the West Indies. Prior to the latest 
Miocene the details of composition and history were entirely dissimilar, 
and unlike the events of Eocene and Oligocene history of the Great 
Antilles, 
During all these epochs from the Eocene to the present the volcanoes 
of the Caribbee chain have been piling up the vast heaps of stratified 
tuff that form not only the eminences but much of the extensive sub- 
marine platforms of the region. 
The island of Barbados, standing 125 miles east of the main Wind- 
ward circle, and separated from it by over 2,000 fathoms of water, 18 
entirely unlike the Antillean, Windward, or Central American provinces 
in history and geomorphology. It has no known volcanic rocks, 
These facts concerning the geology of the Lesser Antilles clearly show 
that piling up of volcanic material began there as far back as the Eocene 
epoch, and that the islands have participated in the later epeirogenie 
movements of Pleistocene or recent time. Hence we may conclude : — 
1. The Windward Islands represent a distinct volcanic province, dis- 
similar in lithologic composition from the older volcanic phenomena of 
the Antillean province, and somewhat similar to the volcanic summits of. 
Central America. 
2. Their visible history dates back at least as far as Eocene time, and 
their periods of greater eruptivity ceased in the Pleistocene. 
PART VI. 
Changes of Physiography in Tropical America, bearing 
upon the History of the West Indian Islands. 
The interpretation of the present configuration and history of the An- 
tillean and Central American regions is a difficult task, and involves 
the analysis of many groups of data, embracing several distinct fields 
of research. Biology, paleontology, oceanography, structural geology 
