Corals and coral islands.

STR UCTURE OF CORAL ISLANDS.

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two feet or more. They live just under the sand in the shallow waters, with the head projecting and bearing a beautiful
feathery rosette or flower which is branchial in nature. To
fit them for exportation, the holothuria, of which half a dozen
different kinds are taken, are slit open, boiled, and then dried,
in which last state they look like "smoked sausages. Dr. S.
Wells Williams says, in his "Middle Kingdom," that "when
soaked in water, the material resembles pork rind, and is like
that in taste when stewed." They are brought to China by the
Malays from Macassar, and elsewhere. There are also large
drying-houses at the Feejees, and ships from America make
their occasional visits to collect them, with the aid of the Feejees, and to dry and load up for China. The term biche de mar,
and also the French form of it, beche de mer, are corruptions of
the Portuguese bicho do mar, which means sea-worm or sea-sluq.
II. STRUCTURE OF CORAL ISLANDS.
I. FORMS AND GENERAL FEATURES.
Coral islands resemble the reefs just described, except that
a lake or lagoon is encircled instead of a mountainous island.
A narrow rim of coral reef, generally but a few hundred yards
wide, stretches around the enclosed waters. In some parts
the reef is so low that the waves are still dashing over it into
the lagoon; in others it is verdant with the rich foliage of the
tropics. The coral-made land, when highest, is seldom more
than ten or twelve feet above high tide.
When first seen from the deck of a vessel, only a series of
dark points is descried just above the horizon. Shortly after
the points enlarge into the plumed tops of cocoa-nut trees, and
a line of green, interrupted at intervals, is traced along the
water's surface. Approaching still nearer, the lake and its belt
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