258 BULLETIN OF THE 
Flat, marshy alluvial deposits (cienagas) occur in many places, but 
mostly on the south coast. At Batabanos, opposite Havana, the coast 
for a mile or more inland is composed of ancient alluvial material, ap- 
parently similar to a calcareous mud now depositing and forming the 
bottom of the adjacent sea for a mile out from land. These cienagas 
and cienaga deposits are reported to have considerable extent at various 
places, especially on the south coast. The elevated portion is synchronous 
with the soboruco elevation on the north coast. 
A striking peculiarity both of the older structures and the coast 
deposits of Cuba is the scarcity — almost total absence — of arenaceous 
or sandy deposits. Nowhere is found the fine quartz sand such as 
accumulates around the northern littoral of the Gulf of Mexico, and the 
presence of pieces of quartz gravel is very rare, even in the delta deposits. 
This is owing to two reasons: (1) the formations of the island, both the 
older metamorphic foundation and the limestones, possess very little free 
quartz, and (2) the littoral sands or physical sediments of the peripheral 
drainage of the Gulf, derived from the continental Americas, are not 
transported as far as Cuba, as Professor A. Agassiz has already pointed 
out. Even the building sand of Havana and other places is calcareous 
beach debris. 
Reefs. — No description of the geology of Cuba would be complete 
which stopped at the ocean level, without allusion to the adjacent sub- 
merged coral reefs that fringe its shores or lie a short distance away, 
which, with the adjacent submarine topography, have been so ably 
described by Mr. Agassiz.! So fully has he described these phenomena 
that it is not necessary to discuss them further, except to call atten- 
tion to the fact that there are often considerable depths between the 
barrier reefs and the near-by land. This has important bearing upon 
the topography of parts of the coast. 
II. GEOLOGIC HISTORY RECORDED BY THE 
TOPOGRAPHY. 
General Topography. — Having reviewed the fundamental rock struc- 
ture upon which the sculpture of the land is dependent, we can now pass 
to a more intelligible discussion of the general topography and its evo- 
lution. It is neither necessary nor possible to give a minute detailed 
description of the geography of Cuba, but only so much as may relate 
1 Bull. Mus. Comp. Zodl., Vol. XXVI. No. 1, December, 1894. 
