1895.] Geology and Paleontology. 271 
The leaf scars were ovo-rhomboidal, and to each there appear to 
have been three bundles of vessels. 
In consequence of this discovery, Mr. Etheridge reviews the history 
and structure of Glossopteris, giving its range in Australia, and points 
out its relation to allied genera. (Proceeds. Linn. Soc. N. S. W., Vol. 
ix, 1894.). 
Geological History of the West Indies.—Mr. Charles T 
Simpson gives a brief history of the West Indian archipelago since 
Eocene times, basing it upon a study of the molluscan fauna of that 
region. He premises his remarks with the statement that a consider- 
able portion of the land snail fauna of the Greater Antilles seems to’ 
be ancient and to have developed on the islands where it is now found, 
while that of the Lesser Antilles has resulted from migration mostly 
from South America. The distribution of the terrestrial and fluvia- 
tile molluscan fauna is carefully worked out and presented in tabular 
form. From the facts collated the author deduces several interesting 
conclusions which he recapitulates in the following form. 
“ There appears to be good evidence of a general elevation of the 
Greater Antillean region, probably some time during the Eocene, 
after most of the more important groups of snails had come into ex- 
istence, at which time the larger islands were united, and there was 
land connection with Central America by way of Jamaica and possi- 
bly across the Yucatan Channel, and there was then a considerable 
exchange of species between the two regions. At some time during 
this elevation there was probably a landway from Cuba across the 
Bahama plateau to the Floridian area, over which certain groups of 
Antillean land molluscs crossed. At this time it is likely that the 
more northern isles of the Lesser Antilles, which seem to be volcanoes 
of later Tertiary and Post-Pliocene date, were not yet elevated above 
the sea, or, if so, they have probably been submerged since. After 
the period of elevation there followed one of general subsidence. 
“During this the island of Jamaica, as the character of its land 
snail fauna shows, as well as the depth of the channel between it and 
Haiti, was first to be isolated, then Cuba, and afterwards Haiti 
and Puerto Rico were separted. The connection between the Antilles: 
and the mainland was broken, and the Bahama region, if it had been: 
previously elevated above the sea, was submerged, the subsidence con- 
tinuing until only the summits of the mountains of the four Greater 
Antillean islands remained above water. Then followed another 
period of elevation, which has lasted, no doubt, until the present time; 
