PEARL-CULTURE AND PEARL-FARMING 289
If
taken up within a few days and examined, the nuclei will be found
attached to the shell by a membranous secretion ; later this appears to
be impregnated with calcareous matter, and finally layers of nacre are
deposited around each nucleus, the process being analagous to the
formation of calculary concretions in animals of higher development. A
ridge generally extends from one pearly tumor to another, connecting
them all together. Each month several tubs of night soil are thrown
into the reservoir for the nourishment of the animals. Great care is
taken to keep goat excretia from the water, as it is highly
detrimental to the mussels, preventing the secretion of good nacre or
even killing them if the quantity be sufficient. Persons inexperienced
in the management lose ten or fifteen per cent, by deaths ; others lose
virtually none in a whole season.
In
November, the mussels are removed from the water and opened, and the
pearly masses are detached by means of a knife. If the matrix be of
nacre, this is not removed ; but the earthen and the metallic matrices
are cut away, melted resin or white sealing-wax poured into the cavity,
and the orifice covered with a piece of shell. These pearly formations
have some of the luster and beauty of true pearls, and are furnished at
a rate so cheap as to be procurable by almost any one. Most of them are
purchased by jewelers, who set them in various personal ornaments, and
especially in decorations for the hair. Those formed in the image of
Buddha are used largely for amulets as well as for ornaments. They are
about half an inch long, and while in the shell have a bluish tint,
which disappears with removal of the matrix. Quantities of them are
sold as talismans to pilgrims at the Buddhist shrines about Pooto and
Hang-chau.
In
some shells the culture pearls are permitted to remain by the Chinese
growers, for sale as curios or souvenirs; specimens of these have found
their way into many public and private collections of Europe and
America. These shells are generally about seven inches long and four or
five inches broad, and contain a double or triple row of pearls or
images, as many as twenty-five of the former and sixteen of the latter
to each valve. That the animal should survive the introduction of so
many irritating bodies, and in such a brief period secrete a covering
of nacre over them all, is certainly a striking physiological fact.
Indeed, some naturalists have expressed strong doubts as to its
possibility, supposing the forms were made to adhere to the shell by
some composition ; but the examination of living specimens in different
stages of growth, with both valves studded with them, has fully
demonstrated its truth.
It
is represented that in the northern part of the Che-kiang province
about five thousand families are employed in this work in connection
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