Daily Kennebec journal. [microfilm reel] (Augusta, Me.) 1870-1975, 1892-11-21
LUMINOUS FISHES.
A SEA ANIMAL THAT CARRIES
POWERFUL SEARCHLlGHT.

Creatures whicl, Inhabit the Deep Are
Endowed by Nature with the Means o.
Finding Their Way About in the Dark
How They Use Their Ocean Lamps.
Government biological laboratories
at Woods Holl and elsewhere along the
coast have been very busy studying
fishes and other creatures that live il
the sea. Sculpins engaged much o.
their attention. One species, known n
the sea robin" has pectoral fins re
sembling hands. They are discovered
to be actually organs of touch, and thu
fish walks on them over the bottom
feeling for its food as it goes. The slime
of these toad fishes" us fishermen cal
the family, is secreted by rows of glands
All fishes have slime secreting organs
In those which live in the depths Of thu
ocean, where is inky darkness. the slime
Glands are so modified as to be trans
formed into phosphorescent spots, thu
slime being luminous. Thus the finn,
dweller in the dark, unfathomed cave:
of ocean carries light about with it t.
see by
One species recently discovered i:
called the mi3shipman. 1t has luminous
disks along its sides and belly, on its
head and at the base Of its back fin. In
fact it is as profusely decorated will
lights as % miishipman is with but
Conscience the name. Each of thes,
luminous disks is complete bullseyt
lantern on Il small scale, having a lens
for concentrating the rays and reflect
or behind ii composed of siliceous spic-
ules. The light comes from layer OF
phosphorescent cells between the re
dector and the lens.
No other known fish has such al
equipment for illuminating purposes
There are u good many species which
nave rehectors without lenses, Will,
others have lenses without refiectors IL
brighten the glow of their luminous
spots. But the midshipman is the only
marine dweller thus far discovered
which possesses both reflector and lens
1t is veritable animated assemblage OF
lanterns. There is a wide variation
among deep sea fishes as to their manner
Of carrying their lights. One kind has
a barbel hanging to its chin, on the end
of which is suspended what might bt
llkened to an electric bulb. while an
other sort upholds it's light over its
head on the highest point of its back
fin In certain species it is believed that
the luminous mucus from the modified
slime glands keeps running continually
down the sides of the fish, rendering the
whole animal brilliant.
1t is considered likely that these Ian
tern bearing fishes of the depths, which
are chiefly head and mouth and highly
carnivorous, are able to turn their lights
on or off at will. This seems probable
on account of the nerves and blood yes
sells communicating with the slime
glands. which have no other apparent
purpose. Thus the midshipman may
have his power, on approach of an enc
my. to suddenly extinguish his torches
whereas, when seeking prey, he can
throw out search lights and brilliantly
illuminate his neighborhood. This phos.
phorescent light is similar to that Of
frefies. which Professor Langley, OF
the Smithsonian institution, declares to
be the most economical and perfect 0.
all known lights, giving the greatest
illumination with the least waste and
without perceptible heat. 1t would be
of enormous value to mankind if the
secret of this light which the fishes use
g., &l,..,. HI, 40,
the ocean could be discovered. Cnfor-
tunstely the nature of it is wholly a
mystery. all efforts to find it ont having
thus far proved unavailing.
Sharks have lately been affor,iing con
tributions to science. The biologists
have been rivisecting them for the pur-
pose Of finding out about the functions
of the ear. which in fishes is made to
some extent on the same pattern as in
man. The fact has been known for
some time that the ear is not merely an
organ of hearing. 1t has to do with the
sense of equilibrium. Light has been
thrown on this matter by removing por-
tons Of the auditory apparatus of sharks.
which are thus rendered unable to main
tain their balance in the water The
part on which this faculty seems to de-
pend is the Labyrinth" and the same
effect is produced by cutting the nerves
communicating with it.
Science is paying much attention now
to the observation Of marine forms, be-
cause the animals that dwell in the
ocean are the oldest in existence. Ac-