The Hawaiian gazette. [volume] (Honolulu [Oahu, Hawaii]) 1865-1918, 1875-10-06
HAWAIIAN GAZETTE
AN INDEPENDENT JOURNAL,
DEVOTED TO HAWAIIAN PROGRESS.
The Ship-Worn.

The world is indebted to NJ. Quaterfages, the
eminent French naturalist for a knowledge Of
the life history Of the Te1eClo ufralis, properly
called the ship-Worm. This destructive little
animal makes its home in submerged wood, which
it perforates with tubular galleries. where it spends
its life alternately tunneling and feeding on the
fine raspings or chips it makes. Il abounds 10
the seas and its ravages are so extensive and SO
rapidly effected that oil submarine structures o.
wood are liable TO be riddled by it unless care.
fully projected against its operations. Planks
and limbers Of bridges, piers and ships, that ap-
pear outwardly whole and perfect will often on
examination prove to be internally furrowed in
every direction and ready to crumble in pieces
under the slightest weight. A piece Of deal has
been found completely riddled in iorty days after
its immersion. NJ. Qaaterfages relates that a
boat raised four months after it had foundered on
the coast near Port ST. Sebastin was SO worm
eaten that it was utterly useless.
The curious part Of the Teredo's tunneling is,
that, although its galleries may perforate every
part Of the wood and destroy its entire substance,
they never communicate. Some instinct informs
the little miner when it has reached a furrow hol
lowed by some other individual, and it instantly
changes its course and literally worms its way in
new direction. 1t generally moves with the
grain unless it meets with some obstruction.
Early in the eighteenth century the Teredo at
tackled the dikes Of Holland and for time threat
ened to annihilate the country by consuming the
piles supporting the sea walls, and thus letting
the ocean roll in upon the land. A vast sum Of
money was expended before the imminent danger
was arrested. But protection against the Teredo
has been found in iron rust Timber exposed to
its cravings is rendered safe on being impregna-
ted with oxide of iron. Copper sheathing is en-
ployed to protect ships, or the timber ia driven
full Of short broad headed nails the rust of which
covers it with q coating which is to the Teredo
like an armor Of mail. Its little teeth never at
tempts to penetrate material SO spoiled for its
taste.
Although the Teredo is called worm, it is re-
ally an acephalous mollusc, and wears from its
birth little biyalve shell. But in the progress
from infancy to maturity it undergoes singular
transformations. 1t is Matched from a small,
round, yelowish-green egg. and is at first naked
and motioness. 1t is soon covered with vibra-
eight hours At the end of this time the ella
disappear and the young Teredo sinks to the
bottom. Here, in the course Of FIVE and a half
days, it develops a ahell tina: almost entirely H.
clJses it. Then it gradually puts forth long
slender foot that projects far beyond the shell,
ana by which it can prOpe itself AT this stage,
it is the size Of grain Of millet, is spherical in
form, and brown in hue, and can swim freely
again, or walk by means of its foot. Now it hunts
about for some fixed or floating wood that is 10
afford it food and shelter, that is to be at once its
castle and IFS larder.
When 1t has found the material necessary to its
existence, it creeps along the surface Of the wood
until it discovers part sufficiently soft and po-
rous, when it begins boring gallery for its future
home. After the tunnel is deep enough to con-
tain it, the little round mollusc rapidly effects q
metamorphoss. 1t covers itself with Shiny
coat that at the end of three days becomes quite
solid. A new and larger shell is next secreted,
after which the Teredo changes its spheroid form
FOR one elongated like worm. Itrequrres about
three weeks for this singular transformation to be
completed. Prof. Verril states that on the coast
Of New England the Tsredo niUaliS produces its
young in May, and probably through the greater
part or all Of the Summer. According to Quat-
erfages, the TeredU's life is rounded in a single
season. 1t perishes during the winter succeeding
its birth