Evening star. [volume] (Washington, D.C.) 1854-1972, 1890-11-22


derives its brilliant metallic luster from the
presence Of many crystals composed of lime
and a substance known as 'guanin.' This coat
ing Is easily rubbed off and in one sort of Eu-
ropean carp, called the bleak the crystals are
SO numerous that a metallic pigment is derived
from them, known in the arts as argentine. >
which is used to impart luster to the glass
globules sold under the name of Roman pearls.
When the silvery coating is absent the scales
OF fish are lusterless and transparent, as in
the case of the smelt, the abdominal cavity of
which, however, has a brilliant silvery lining
composed of the same substance.
"E cry one knows from observation that the
fishes OF the world are most gorgeous of all
animals in point of coloring. The colors thew
exhibit are often due to a simple Arrangement
of pigment cells, but the brilliant and change
able hues which constitute the greatest beauty
OF these creatures are derived from two causes
very wide apart. An illustration of one of
these may be observed in the scales of the her
ring. shad or mackerel, being true irdescence
similar to that seen in the pearl and due to
the refractiOn of the rays of light az tley
glance off the surfaces of the thin plates OF
which the scales are composed. More i'm
portantly. however, the celebration is dependent
on the arrangement OF the pigment cells that
lie in the lower layers Of the outer skin Of the
fish.
"In fish, when the black pigment which
predomnates, the color is somber, as in tho
adult tautog. A slight admixture of yellow
gives the bronze-like hue of the eel, and lit
tie more of the same, if you please, results in
the brighter green of the black bass and the
blue fish. Red pigments intermixed with black
give the dingy brown OF the carp and some of
the catfishes. When the yellow and red out
number the black cells there result the tawny
colors of the snnfishes, the cusks and of some
varieties Of the cod. Red pigment cells in the
lower strata of the outer skin alone cause the
brilliant scarlet of the red snapper and the
rosefish, and when these are interpreted with
black, the deeper colors OF the mangroye
snapper and the rudy variety of the sea raven
result. When the pigment cells gather into
separate groups according to color, bands,
stripes. spots and standings, infinite in their
variety are found.
In fish. as in other animals, albinoes occur.
Very curious are the albino haddOcks occa-
sonally taken on our coasts. The same phe-
nomenon is also observed in founders carp
and eels In the depths OF the sea, where light
is scanty, many fishes appear to remain perma-
nently albinoes.
Fishes very commonly change their colors
to harmonic with the bottoms on which they
live, for the sake of conceaiment This is ac-
complished by the special secretion of the
proper pigments On certain lodges along the
New England shore the rock are covered with
dense growths Of scarlet and crimson seaweed,
and the fishes which frequent their neighbor.
hood become tinted accordingly. 1t has been
suggested, by the way, that the pink Of the sal
mons flesh is due to the absorption of the
coioring matter of the crustaceans they feed
upon. Probably the brilliant celebration of
many kinds OF fishes is designed by nature to
attract the opposite sex. as the beauty of q
peacock's tail is intended for the same pur-
pose. Fear or other emotions will often change
tho colors OF fishes rapidly.
TT is in tropical seas that the most bril-
liantly colored and beautiful fishes of the
world are to be found. Warmth and light are
favorable to brilliancy and variety OF hues al
ways The fishes of the polar regions and
those living at considerable depths are usually
somber. and when you get down to the dark
abysses Of the ocean they arc all black"