7 
MUSEUM OF COMPARATIVE ZOOLOGY. ABT 
Quarries of cantera are found adjacent to most of the cities on the 
north coast of the west half of the island. They occupy a slightly 
higher altitude than the coast reef, and usually constitute the first 
bench of the island above it at a lower level than the erosion planes in 
the older limestones. (See Havana and Matanzas sections, Plate I. Fig. 
1. 2, and Fig. 4. 1.) 
I did not observe any break between the cantera and the older lime- 
stone, owing to obscurement, except in the Matanzas section, where it 
clearly appears that the cantera is mostly old reef rock which has no 
topographic integrity, and which was unconformably deposited on the 
older limestone after the latter had been considerably elevated. In other 
words, it there represents the oldest of the recognizable fringing reefs. 
At Havana, in the convict quarry, northwest and at the foot of the 
Castillo Principe Plateau, which is made up of the older limestone, there 
is a great cantera that seems more molluscan than coralline. The same 
deposit is also worked in the banks of the Rio Armendaris, two or three 
miles southwest. Topographically it here underlies an erosion level 
intermediate in height between the level of the modern reef and that of 
the Moro Plateau. No cantera was observed east of Matanzas in the 
ports of Segua, Gibara, Nuevitas, or Baracoa. It is not here proposed 
to establish the cantera as a persistent geologic unit, for there may be 
other cantera beds in the old limestone. The coralline cantera of Ma- 
tanzas and the molluscan cantera of Havana are not found at an alti- 
tude of more than one hundred feet, and they are always near the coast. 
At the former locality the cantera is the oldest of the rocks of prob- 
ably coralline origin, and at the latter it is intermediate in position 
between the modern reef rock and the older limestone. 
Throughout Spanish America the term “playa,” meaning literally 
a flat beach, lacustral, or shore deposit, is applied to alluvial flats or 
mud plains composed of gravel, sand, and clay. In Cuba I found that 
the term was generally used for an alluvial deposit sometimes lining the 
inner margin of the circular harbors, as at Havana and Baracoa. These 
are small in area, and are usually adjacent to the zone at which the 
rivers come out of the highland into the harbors; they represent delta 
deposits that have undergone slight elevation coincident with that of the 
modern elevated reef. Their origin is more fully discussed under the 
head of Harbors. 
1 Specimens of this cantera received from Havana since this report was written 
somewhat confirm the impression that they represent a late Post-Pliocene deposit laid 
down against the older Tertiaries, and prior to the elevation of the soboruco, 
VOL. XVI. — NO. 15. 17 
