272 Pearls.
America, in the Bahama Islands, in the Yagr river, and at Acapulco, in Mexico, and also in the Gulf of California. It is seen, therefore, that fresh water as well as marine shells may yield pink Pearls but those of fresh-water origin are of a more rosy pink colour. The principal shell which produces these beautiful objects is the great Strombus gigas.
The genus Strombus represents the typical form of the family of Strombidce, and consists of about sixty
species, which inhabit the West Indies, Mediterranean, Red Sea, India,
Mauritius, China, New Zealand, the Pacific and Western America.
The SHrombus gigas,—the '* fountain shell " or " conch shell " of the West Indies—is one of the largest
living shells, some specimens weighing as much as four or five pounds.
Immense quantities are annually imported from the Bahamas, for the manufacture
of cameos, and for use in porcelain manufacture. According to the late
Prof. Archer, 300,000 were brought to Liverpool alone in one year. This
enormous scale of importation will account for our familiarity with the
shell as a household ornament.
It
is this shell also which is generally used by carvers of Italian shell
cameos—for which purpose it is admirably adapted by its delicate tints.
The
