Wausau pilot. [volume] (Wausau, Wis.) 1896-1940, 1904-09-13
SECRET OF OR ENl PEARL,
DISCOVERED TO BE MERELY SEP
uLcHRES OF DEAD PARASITES.

OE@ThG0 VI BEAD TAHRSii ES.
The Gulf Of Manaar, on the Coast of
ceyion, is the Chief Source-Fished
Up by Native Dlvers-Tomb of
Baby Tape Worms.
For more than 1000 years the Gulf
of Manaar. on the northwest coast of
Ceylol, has been noted as the chief
source of Orient pearls. which are
found in the bodies of pearl oysters
(Margaritifera vulgaris), more truly
described, however, as pearl mussels.
The mollusks are fished up by ma
tive divers, though recourse will prob
ably De made to dredging in the fu-
ture. The alarming decline in this
important fishery. the proceeds of
which, amounting TO hundreds of
thousands of rupees annually, have
rong been an important asset in the
revenue of the Ceylon government,
recently resulted in Prof. Herdman of
Liverpool being sent out to ascertain
the cause, and, if possible. to suggest
remedy.
The first volume of his report has
just appeared, and the beneficial re-
suit of his valuable suggestions is
already being felt Mr. James Hor-
nell, well known naturalist, has
been associated with Prof Herdman
in the matter, and is continuing the
work under the auspices of the Colo
NAL Cavern Tho meet intoros+
ing outcome of the whole thing is
the fascinating story which these ex-
perts tell us about the mode of origin
Of oysters tears" Mr.. Hornell has
just ascertaiLcd the facts which make
the story complete
For nearly half a century it mas
been known that river pearls, which
once were the object of important
British fisheries, are caused by the
irritation set up by parasitic worms,
and forty years ago Kelaart proved
that this is also true of the marine
pearls of Ceylon. But it 9las been re-
served for Herdman and Hornell to
work out in detail the story of the
adding one more romance to the fairy
tale book of modern science
Living in Indian seas is voracious
stingray (Trygon), the lnlestines of
which afford food and lodging to pc.
culiar little tape worm (Teirarhyn-
chus). This unwelcome guest holds
on for dear life to the lining of the
intestine by means of two suckers
and FOUR long hooked tubes, project
ing from its head. AS in tape worms
generally, the hind end is made up
of series of fiat joints, within which
innumerable eggs are developed. The
ripe joints pass out of the body of
the fish, and from the eggs minute
free7swimming embryos hatch out.
Some of these pass between the
shells of pearl oysters, burrow into
the bodies of the unfortunate inmates,
and there develop heads. But many
other things must happen ii they are
to get the chance of growing into
adult worms. One of the hereditary
foes of pearl oysters is tie rough
skinned trigger fish (balistesl, which
feeds on the sluggish bivalyes, easily
crushing their hard shells with its
powerful chisel-ended teeth If one
of these fishes happens to deyour an
infested oyster the little parasites
bore through the walls of its stom-
ach and imbed themselves in its flesh,
making it "measily." But the para
site has yet to reach the interior of a
stingray before it can become adult,
and the transfer is often effected, for
the trigger fish is favorite item in
the bill of fare of the stranger ray.
But what has all this to do with
pearls? Here is the answer Many
OF the Juvenile tape worms that infest
the oyster die, and then become a
source of irritation. To allay the tick
ling, layer after layer of pearly sub
stance is formed around them, and in
due course we have pearls. Long-in-
tested oysters, of course, yield the
finest. The economic bearing of these
facts is clear. Stingrays and trigger
fishes alike must be carefully pre-
served" otherwise the tape worm
will become extinct, and then no
pearls, or, at least, none of the best
sort. Some varieties are very posi-
bly, caused by parasites of other
kinds. And small, inferior pearls may
be formed round sand grains OF mi
mute, hard particles due to infiam.
matory disease. In ignorance of the
facts related, it was proposed not
long ago to wage war a Ioutrance
against the trigger fishes because they
devour pearl oysters. If the step had
been taken the government pocket
would have been sorely depleted So,
after all, natural history has it's uses
for practical men," and it is a pity
that our government does not gen.
erously endow scientific research in
this important subject.
The secret of the Orient pearl, as
now revealed, will suggest some Gu
rious reflections to society beauties.
for, as we have seen, some of their
priced adornments are no other than
the gorgeous sepulches of premature.
ly deceased parasites, the tombs of
baby tape worms. 1t is really enough
TO make Cleopatra turn in her grave,
for she swallowed a dissolved pearl.
dead tape worm and all Antony
would surely have shuddered had he
known the facts as we now know
them.