216 BULLETIN : MUSEUM OF COMPARATIVE ZOÖLOGY. 
stone and marls of shallow water origin. The limestones may be of the 
type of the Pliocene Manchioneal formation of eastern Jamaica, which is 
sparse in identifiable molluscan remains, although containing Pteropods 
and Brachiopods and a few thin beds of modern reef corals ; or of the 
Falmouth type, largely composed of shells, in which the remains of a 
certain species of Bulla are specially abundant. I know of the occur- 
rence of all these formations in stratigraphic juxtaposition only in Jamaica, 
although types of each have wide distribution throughout the Tropical 
region at altitudes nowhere exceeding 250 feet excepting in Barbados and 
the inner margin of the Caribbee Islands. 
The oldest and highest group of these levels, composed of no later 
strata than the old Oligocene, may probably have been developed on 
the emerging land between the Montpelier and Bowden epochs of subsi- 
dence. They may present old levels engraved upon the margins of this 
Antillean land during the erosive epochs accompanying and following 
the culminating orogenic uplift. This is the level preserved on the 
summits of the Pan de Matanzas and Yunki of the north coast of Cuba, 
and the 2,000 foot limestone benches against the Sierra Maestra of the 
south side of the same island ; also the John Crow and Yallahs Moun- 
tain levels of Jamaica. 
The middle group may be of late Pliocene and early Pleistocene age, 
while the newer or coastal group, characterized by being largely composed 
of elevated reef rock, is the product of the late Pleistocene or recent 
emergence. . 
After the Bowden subsidence, there was further elevation, which added 
the Bowden formation to the Antillean margins. This was not so in- 
tense in amplitude as the preceding orogenic uplift, but far reaching in 
its effect and geographic importance. The Antilles were expanded to 
areas probably embraced by the present 100 fathom lines, enlarging 
the eastern and southern margins by narrow ribbons of restored land. 
This uplift was greatest on the continental mainland, the movement 
being less felt in the Antilles. 
The whole of the Coastal Plain, with its Appalachian background and 
the Great Plains region of the United States, and probably the Cordilleran 
region also, participated in this upward movement. Southern Florida, 
heretofore West Indian in its relations, was united with the land to the 
north and became populated with North American mammals. The 
island could have had no Antillean or Bahaman connection at this time, 
for these mammals are not found in the latter regions. The elevation, 
however, was not sufficient to establish a united Antillean continent 
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