CanÌƒon City record. [volume] (CanÌƒon City, Colo.) 1883-192?, 1897-11-11
PROPAGATION OF EELS.
A Perplexins Problem Is at Last
Solved
The Manner OF Reproduction for
Hundreds Of Years Unknown
to scientists-Another
Question.

For hundreds of years naturalists
have been seeking in vain to find out
how eels are propagated. The eel
problem worried hundreds of genera
tions, and now at last the secret is
out. 1t has been discovered by two
Italian biologists, Prof. Grassi and his
pupil, Sig. Calandruccio. In order to
reach the source of this discovery we
must go back to 1903. At that time
the naturalist Pennant called attention
TO singular little fish that was then
utterly unknown, and which is still
found at several points in the Atlantic
ocean and especially in the Mediter-
ranean sea. 1t is a little creature as
transparent as glass, with flat body
and very small fins. 1t is almost en-
tirely formed of gelatinous tissue. 1t
has no eyes and its blood is colorless.
For long time it was thought that
it was a species in itself, but nobody
knew where to place it in the family of
creatures. In 1864 an American scien-
tist, Mr.. Gill, stated that these singular
little fishes were the larvae of conger
GELS, and in 1856 professor of the Sor-
bonne, NJ. Yves Delage, confirmed the
statement of Mr.. Gill and proved by
experiments that the little creature
was larva. He put one OF them into
an aquarium, where he witnessed its
transformation into young conger eel.
Now the larvae in question are
plentiful in Sicily, and particularly in
.he straits of Messina. Prof. Grassi
procured number of them and kept
hem for a long time in an aquarium.
With Sig. Calandrucio he witnessed
The metamorphosis of these larvae.
they all became eels, some of them
.ongers and others of different spe-
cies. But there was one particularly
small species which attracted their at
tention. They watched ii closely, and
one day they found it transformed into
a common eel. The greater portion of
the larvae collected by Sigs. Grassi and
Caiandruccio came from great depths,
500 meters at least. These larvae come
to the surface by accident when torn
from their retreats by the currents and
the connections so frequent in the
Straits of Messina. The conclusion.
therefore, is that the production Of the
.rels is brought about very far from the
surface of the sea. The larva of the
eel is about seven or eight centimeters
long, and the young eel, the result
of the transformation, is always
shorter.
We are now, therefore, in position
10 explnin the enigma that baffied the
world from the time of Aristotle Re-
versiug the habit of the salmon, the
eel comes down from the rivers to reach
the sea from October until January.
In the deep water II rndergoes impor-
tant changes, according to the speci-
mems observed by the two italian sci
entists. Its eyes especially acquire di-
mensions that they never attain in
fresh water. The color also changes.
The eggs begin TO float upon the sur
face of the sea in the month of Janu-
ary; but the first larvae do not make
their appearance until the following
spring. These larvae are found in the
stonachs Of fishes that are known to
live in very deep water. They are de-
yeloped in the sea, and it is believed
that it requires at least month be-
fore they are transformed into little
cells. The reproduction in the different
species is slow. 1t In estimated that
there is an interval of two years be-
tween the descent OF the adults from
the rivers to the sea and the return
Of their progeny. Aftersremaining for
a certain time in salt water the young
eel seeks the estuaries, and at last takes
the road TO the rivers. AS for the old
eel, it remains in the sea, and it is the
general opinion that 1t dies very soon
after reproduction. Consequently, 1t
never returns to the fresh water. Such.
in brief. is the mystery OF the cells,
which Profs. Grassi and Calandruccio
have elucdated. There remain now
only a few details to study. 1t took
long time to make the discovery, but
all's well that ends well.
Henri de Parville."
Now, If Profs. Grassi and CalandriIc-
clio will tell us how eels grow in lakes
and duck ponds far from the sea, it
might be interesting reading. 1t is also
strange that in artificial ponds in which
fish have never been placed. II takes
little more than two years to find them
well stocked with various members of
the finny tribe, big and little, according
to the nature OF the soii.--N. Y. Sun.
Hartford also has a plague Of fero-