SECOND ANNUAL REPORT—SOUTHERN EEORIDA. 
225 
The limestone on Lostmans River, though containing calcite crys¬ 
tals an inch long, is not greatly different from other limestones of 
southern Florida; removal, deposition and crystallization of carbonate 
of lime are characteristic of the region. 
The limestone, from its petrographic and paleontologic character¬ 
istics, is a shoal water deposit of marl and limy sand, containing shells 
of living species of mollusks, that has been solidly cemented and sub¬ 
jected to conditions favoring crystalline growth. This growth may 
be in progress. 
COQUINA. 
The word coquina is here used, as it is used on the east coast, to 
designate those deposits of cemented shell fragments and quartz sand 
that can be seen at many localities near the present ocean shore of 
southern Florida. In some exposures noted by the writer the rock bore 
slight resemblance to the long-known occurrences on Anastasia Island, 
being a rather fine-grained dense gray sandstone that rang under the 
hammer. This is probably the rock Griswold saw interstratified with 
coquina (shell rock) near Linton. 
All phases between shell rock and material which is made up 
mostly of quartz sand can be found near Hillsboro Inlet, Delray and 
Palm Beach. At the spouting rocks some miles south of Hobe Sound 
the rock contains quartz grains, coarse and fine, and much worn frag¬ 
ments of shells (including axial pillars of conchs over a foot long) the 
whole so solidly cemented that the seaward face of the ledge worn into 
shallow grottoes, resists the breakers well enough to make a feature of 
unusual interest, the only spouting horn on the Atlantic coast of the 
United States south of Newport, R. I. 
Coquina outcrops at Jupiter Inlet, along the east and west shores of 
Lake Worth, at Boca Ratone and at Hillsboro Inlet. It was found in 
the Florida Coast Line Canal at the cut to Indian River, the cut below 
Hillsboro Inlet and near Boca Ratone. The ledges seldom make rock 
knolls, though east of Hobe Sound are several knolls, the highest ac¬ 
cording to Mr. Grant of the Indian River Association, who has sur¬ 
veyed much of the island, having a maximum elevation of thirty feet 
above sea level. Its greatest extent inland is undetermined; as expos¬ 
ures seem to be confined to localities within a few miles of the beaches, 
it may be represented inland by unconsolidated material. In the canal 
south of Hillsboro Inlet the coquina apparently extended over fossil 
coral heads. No ledges of rock resembling the east coast coquina have 
been reported from the west coast of southern Florida. 
The predominance of well-worn material in the coquina indicates 
an origin from sands that accumulated on barrier beaches or on bars 
when the surf had full swing. Certain features of the outcrops east 
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