are called Shore-Reefs. There are also Barrier-Reefs, usually
enclosing an island in the deep sea, and Lagoon Islands or Atolls,
which enclose a lagoon, or lake, such as the one where Sammy now was.

Near the centre of this Lagoon arose another ring of coral-reef, like
a small circle within a larger circle, and in the centre of the second
little lake so formed, was a tiny coral-island, dotted here and there
with gay flowers, and waving palm-trees.

Outside the reefs the white-topped breakers thundered on unceasingly,
but the calm waters of the Lagoon were undisturbed by their fury. Far
above and below towered the magnificent rocks, forming so complete a
barricade that sharks and very large fish found it difficult to gain
an entrance to the Lagoon, and could never penetrate to the inner
lake, where the inhabitants of Coral-Land sometimes took refuge.

As for the smaller fish, the reefs were punctured with innumerable
little passages and caverns through which they could easily gain
access to the outside ocean, if they wished, but most of them
preferred the quiet and security of the Lagoon. Many had been born
there and knew no other life, and many, like the Sun-Fish had grown so
fat with good living that it would have been almost impossible for
them to squeeze through the largest opening.

In fact the Lagoon was like a large aquarium of curious and beautiful
fish. Floating lazily along was a round, prickly Globe-Fish, and close
behind him drifted a cross looking Porcupine-Fish, an odd, countrified
sort of creature, with his gaping mouth, the sharp spines on his ugly
body raised in preparation for a possible attack from the strangers.
Away off among the distant rocks some dazzling Gold-Fish chased each