The Ketchum keystone. [volume] (Ketchum, Idaho) 1885-1899, 1897-10-30
PROPAGATION OF EELS.
A Perplexinc .-roblem = at Last
Solved



"For Aundssds Of ysasu naturalists
have been seeking In vain to mud out
how eels are propagated. The eel
problem worried hundreds of genera
tions. and now st last tho secret Is
out. It 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 80 back to 1863. At that time
the naturalist Pennant called attention
to . singular little fish tha. was then
utterly unknown, and which 10 still
found at several points In the Atlantic
ocean and especially In the Nediter-
nnean sea. It 10 . little creature as
transparent - glaw. with . fat body
and very small inns. It il almost en-
tirely formed Of . gelatinous tissue. It
has no eyes aud it, blood il colorless.
For . long time 1t was thought that
it was . species in itseif, but nobody
knew where to place It in the family Of
creatures. In 1864 m American scien-
tist, Mr.. Gill, stated that these singular
little fishes were the larvae Of conger
esls, and In 1866 professor OF the Sor-
bonne. NJ. Yves Delage, confirmed the
statement Of Mr.. Gin and proved BY
experiments that the little creature
was hrvs. he put ono Of them into
an aquarium, where he witnessed its
transformation into young conger eel.
snow the larvae in question are
plentiful In Sicily, and particularly In
the straits Of Messina- Prof. Grassi
procured q number Of them and kept
them for . long time IN an aquarium.
With Sig. Calandrucdo he witnessed
The metamorphoais Of these larvae.
They al became eels, some of them
oonCen and Others Of di6erent spe-
cieo. But there was one particularly
small species which attracted their at
ten&ion. They watched it closely, and
one day they found it transformed into
common eel The greater portion of
tho larvae collected by Sfgs. 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 20 frequent in the
Straits Of Messina. The conclusion,
therefore. II that the production of the
eels II brought about very far from the
surface OF the sea. The larva Of the
eel II about seven or eight centimeters
long, and the young eel, the result
OF the tran&ormation. Is always
shorter.
I'VE are now, therefore, in position
70 explin the enigma that bafaed the
world from the time of Aristotle. Re
vensing the habit of the salmon. the
eel comes down from the rivers to reach
the sea from October until January.
In the deep water 1t undergoes 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 doat upon the sur
face Of the sea in the month of Janu-
ary; but the Arst larvae do not make
their appearance until the following
spring. These larvae are found in the
s4omachs Of hahes that are known to
live In very deep waber. They are de-
veloped in the sea. and it II believed
that it requires at least month be-
fore they are transformed into little
eels. The reproduction in the different
species il slow. It II estimated that
there 10 an interval Of two years be-
tween the descent Of the adults from
the rivers to the sea and the return
of their progeny. After remaining for
4 certain time in salt water the young
eel seels the estWries. and at last takes
the road to the rivers. As for the old
eel. It remains in the sea, and It 10 the
general opinion that 1t dies very soon
after reproduction. Consequently. It
never returns to the fresh water. Such,
N brief, Il tho mystery Of the eels,
which ProAs. Grasd and Calandruccio
have elucidated. There remain now
only . few details to study. 1t took ,
lonsr time to make the discovery, but
all's well that ends well.
"Henri de Parville."
Now. II Profs. Graasi and Calandruc-
e3o win ten ~ how eels grow in Akes
and duck ponds tar from the -. u
might Be interesting reading. It u ano
strange that In artificial ponds IN wnicn
Ash have never been placed. 1t taxes
nttle moro than two years to find them
well stocked with various memoero OF
the dnny tribe, big and little. according
"a the nature Of the soiL-N. 7. sun.
A. ~A> Pnnana Canal.
..The Panama canal project u being
nushed with considerable energy. ana
& 49,. =. <hou1h there were good rc0r