HABITAT OF THE PEARL OYSTER
Sea are no fisheries save at Haiti, for no discoveries of any importance have been made on the western coast of Africa.
Consideration
of these homes of the pearl oyster shows it to be a tropical fish and
that it attains greater dimensions in the Pacific Ocean and near the
equator than elsewhere. Beyond 30 degrees north it is found only at two
points, the western shore of America and on the Japanese coast. These
shores are washed by equatorial currents. The small varieties of the
Indian seas and Venezuela, mature rapidly in four to six years, and if
not taken they die out after the seventh year. The meleagrina of the
Pacific however, though it attains its full size in six to eight years,
continues to lay on shell-nacre up to twelve and even twenty years. A
shell which is of good size but comparatively thin is called by the
dealers in mother-of-pearl a "young shell." The Australian pictured at
page 129 is such an one. The Tuamotu at page 127 is not full grown but
well along in years, probably fourteen to sixteen years old.
Of the sea mollusks yielding formations which, though not true pearls, are so called,
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