SALT-WATER FISHES
We now come to the fishes of the sea; and at the head of these we may
place the sharks.
These savage and voracious creatures are found in all oceans, the larger
ones wandering very widely, while the smaller ones are restricted to
limited parts of the sea. Among the latter are the various small sharks
called dogfish, from eighteen inches to six feet long, found on both
sides of the North Atlantic. Though small, and harmless to man, the
dogfish really is a shark, and for its size is very formidable, being
able easily to fight and kill fishes quite as large as itself.
It is called the dogfish because it follows shoals of fish in the water,
just as a wild dog will follow the animals on which it preys upon dry
land.
When you are staying at the seaside you may sometimes find the dead body
of a dogfish lying on the beach, where it has been flung by a very high
wave. And you will notice how coarse and rough its skin is. This skin is
often used for covering the handles of swords, as it gives such an
excellent grip; and also for putting on the sides of match-boxes instead
of sandpaper.
But even if you do not find the dogfish itself lying on the beach, you
may often find its eggs, which are very curious little objects. They are
something like oblong horny purses, of a yellowish-brown color, with a
long twisted appendage at each corner, very much like the tendrils of a
vine. By means of these the egg is anchored down to the weeds at the
bottom of the sea, and they hold so firmly that they are hardly ever
torn away, except during a violent storm.
At each end of this singular egg is a narrow slit, through which water
can pass to the gills of the little fish which is lying inside it. And
one end of the egg is made in such a manner that when the fish is ready
to hatch it can easily push its way out.
THE BLUE SHARK
A much larger and more dangerous fish, which often visits northern seas,
is the blue shark, which sometimes grows to a length of fifteen or
sixteen feet. It does not often attack human beings, however, but is
very destructive in our fisheries, snatching away fishes which have been
hooked, and even swimming along the outside of the nets as they are
being drawn in, and biting great holes through them, in order to get at
the pilchards or herrings within. So the fishermen always kill a blue
shark if they have the chance of doing so, and sometimes destroy eight
or ten in a single day.
But it is not very easily caught, for if it is hooked it will often bite
the line asunder, and if it cannot do this will roll round and round in
the water coiling the line round its body, when it will snap with a
sudden jerk. Even when it is caught, the blue shark is not killed
without much difficulty, for it thrashes its great powerful tail about
in such a manner that it cannot be approached without danger. So the
first thing that the fishermen always try to do when it is captured is
to chop off its tail with an ax.
The color of this shark is slaty blue above and white beneath.
THE WHITE SHARK
Even larger and more dangerous still, the great white shark, or
Rondeleti's shark, is one of the most formidable creatures that roam the
seas. It often grows to a length of thirty-five or even forty feet, and
weighs ten or twelve tons, while one snap of its huge jaws will shear
off a man's legs or cut his body in two.
This enormous fish is found in all the warmer parts of the sea; and in
general sharks, and especially the large ones, belong to the tropical
rather than to the colder seas.
THE HAMMERHEAD
A huge and much-to-be-dreaded creature, of curious appearance, this fish
has its head formed just like that of a hammer, the eyes being
placed at each end of the projecting lobes. It grows to a length of
fifteen or sixteen feet, and is very fierce and savage, attacking human
beings without the least hesitation. It is nearly always found in the
tropical seas, but has been several times captured off the coasts of New
England.
THE THRESHER
Growing to a length of ten or twelve feet, the thresher is a remarkable
shark. It is common in the Mediterranean Sea and the Atlantic Ocean. It
feeds chiefly upon herrings, darting into the midst of a shoal and
snapping them up in hundreds.
What it is specially famous for, however, is its habit of attacking
whales. For this purpose several threshers will unite together, leap up
into the air, and strike tremendous blows with their long tails upon the
whale's body as they fall back into the sea. This naturally terrifies
the whale, and he dives under water in order to escape from his
tormentors. Knowing that he must very soon rise again, however, they
wait for his reappearance, and then attack him again in the same way.
This happens again and again, until he is quite worn out by his
exertions, and by the impossibility of remaining long enough at the
surface to breathe properly. Then if any swordfishes happen to be in the
neighborhood, they come and attack him too, driving their long swords
deep into his body. Before long the whale is dead, and both threshers
and swordfishes are tearing great strips of flesh from the carcass and
greedily devouring them.
SAW-FISHES
Next to the sharks come the saw-fishes, which have the upper jaw drawn
out into the form of a long, narrow beak, set on either side with a row
of large, pointed teeth. So it really looks very much indeed like a saw.
The fish uses this curious weapon by dashing into the midst of a shoal
of smaller fishes and striking them right and left with its saw. In this
way it is sure to disable a good many, which it then swallows leisurely
one after the other.
Saw-fishes are found in all the warmer seas, and sometimes grow to a
length of fifteen or twenty feet.
RAYS
The rays have broad flattened bodies, and very long and slender tails.
In consequence of this structure they cannot swim by means of their
tails, as nearly all other fishes do, but travel slowly through the
water by waving their side fins, after the manner of soles and
flounders.
One of the best known of these fishes is the skate, which when fully
grown sometimes measures as much as six feet in length from the snout to
the tip of the tail, and five feet in width of body. As it cannot swim
fast enough to overtake other fishes, it preys chiefly upon crabs,
lobsters, and shell-bearing mollusks, which it finds on the bottom and
is able easily to crunch up, shells and all.
The eggs of this fish may be found in great numbers on the sea-shore.
They are very much like those of the dogfish, but are nearly black in
color, and instead of a long twisted tendril at each corner, they only
have a blunt projection about an inch long. They remind one, in fact, of
a hand-barrow, and consequently the fishermen often call them
"skate-barrows."
In color, the skate is grayish brown above and grayish white beneath.
Another very curious ray is the torpedo, which is an electric fish,
having a kind of electric battery inside its body, from which a very
powerful shock can be discharged at will. This battery, in appearance,
is something like a honeycomb, consisting of a number of six-sided
columns, which run from the skin of the back to that of the lower
surface of the body. Each of these columns is divided into a number of
cells, or chambers, by thin walls of membrane; and each cell contains a
liquid which seems to consist chiefly of salt and water.
The electricity produced and stored up in these organs seems to be
discharged along four great nerves, which run from the battery up to the
brain. The shock is sufficiently strong to kill a duck; and not only has
an electric bell been rung by it, but an electric spark has been
actually obtained. And when five persons held one another's hands, and
the person at each end laid his finger upon the torpedo, every one of
the five persons felt the shock.
Even more formidable, though in quite a different way, is the sting-ray.
At the base of its long whip-like tail this fish has a bony spine set
with sharp teeth, like a saw; and its favorite mode of attack is to coil
this tail round the body of its victim and then to drive the spine into
his flesh, working it backward and forward in such a manner as to cause
a very serious wound always followed by severe inflammation.
Some of the rays in the warmer seas grow to a very great size; indeed, a
ray measuring over eighteen feet in length has more than once been
captured. They are dangerous creatures to meddle with, for a fish of
this size is quite strong enough to overturn a boat, while if a man were
once seized by one of them, he would have very little chance of escape.
These huge creatures are generally known as devil-fish.
THE STURGEON
This fish belongs to quite a different group, which may be distinguished
by two points. In the first place, its skeleton is made not of bone, but
of gristle; and in the second place, five rows of shield-like bony
plates run along the back and sides of the body, forming a kind of
natural armor.
The sturgeon is often eight or nine feet long, and weighs three or four
hundred pounds. It spends most of its life in the sea, but ascends the
rivers in order to spawn, like the salmon. It is not so common as
formerly in American waters, although sturgeon are taken in nearly all
our larger rivers from time to time; but in some parts of Europe, and
especially in Russia, it is very plentiful.
Caviare is made from the sturgeon's roe. The membranes which separate
the eggs from one another are all removed, and the eggs are then salted
and pressed into small barrels, being afterward eaten as a kind of
preserve.
The best isinglass is made from the sturgeon's swimming-bladder,
which has so much gelatine in it that, if a small quantity is dissolved
in a hundred times as much boiling water, it will form a stiff jelly
when it is cold.
The sturgeon's flesh is very good to eat, for it is not only
well-flavored, but is so firm and solid that it is almost like beef.
In England the sturgeon is known as a "royal" fish, because, in days of
old, when one of these fish was caught in an English river, it was
always kept for the table of the king; and even now, if a sturgeon is
captured in that part of the Thames which is under the control of the
Lord Mayor of London, it belongs by right to the Crown.
THE BEAKED CHÆTODON
A great many fishes are very odd to look at, and this is one of the
oddest. Imagine a fish with an almost circular flattened body, with five
brown bands edged with white running round it, huge round eyes, enormous
triangular fins both above and below the body, a broad tail, which looks
as if it were tied in by a piece of ribbon at the base, and a mouth
drawn out into a long slender beak! And this fish has a habit which is
even odder still, for when it sees an insect sitting on a leaf which
overhangs the margin of the sea, it takes careful aim, squirts a drop of
water at it from out of its long beak, and nearly always succeeds in
knocking it into the water below!
This fish lives in the Indian and Polynesian seas, and is sometimes kept
as a pet by the Japanese, who amuse themselves by fastening a fly to the
end of a piece of stick and holding it over the bowl in which the fish
is living, in order to see it knocked off its perch by a pellet of
water.
THE COD
Throughout the northern seas the cod is found, and in some parts it is
taken in immense numbers. The largest and finest of all, which sometimes
weigh more than one hundred pounds, come from the banks, or shallows in
the sea, off the shores of Newfoundland, but very fine ones have been
taken elsewhere; and extensive cod-fisheries are maintained in
the North Pacific, near Alaska.
Cod are mostly captured by means of long lines, each about forty fathoms
in length, to which a number of smaller lines are fastened at intervals.
The hooks are placed on the side lines, and are generally baited with
whelks, and then the long lines, or trawls, as the fishermen call them,
are anchored in shallow parts of the sea where codfishes, halibut, and
the like abound. Each boat carries about eight miles of these lines,
with nearly five thousand hooks, so that the work of baiting, lowering,
and raising them is very heavy indeed. The fishing takes place in the
winter, and the boats are generally out in all weathers for several
months at a time.
One would think that with so many boats engaged in cod-fishing, each
with so many miles of line, nearly all the cod in the sea would soon be
caught. But to offset this, a single cod in a single year will often lay
eight or nine million eggs, so that notwithstanding the immense number
of these fishes which are taken, they still seem as plentiful as ever.
FLATFISH
The so-called flatfishes, such as the sole, the plaice, the flounder,
and the dab, form an interesting group. Although we call them "flat," we
ought really to call them "thin," because what we always consider as the
back of a sole is really one of its sides, and what seems to be the
lower surface is the other side.
The explanation is this: when these fishes are quite small, they swim
upright in the water, just as other fishes do, and drive themselves
along by means of their tails. But when they are about a month old a
strong desire comes over them to go and lie down on the mud at the
bottom of the sea, and then three remarkable things happen.
First their color changes. Up till now, both sides of their bodies have
been nearly white. But if a white fish were to lie down on dark-brown
mud, of course it would very easily be seen, and most likely would very
soon be devoured by one of its many enemies. So as soon as the
little fish lies down at the bottom of the water its upper surface
begins to grow darker, and before very long it exactly resembles the hue
of the surrounding mud. Or if the fish should lie upon sand, as the
plaice does, then its upper surface becomes colored like the sand. So as
long as it keeps still its enemies may pass quite close to it without
noticing it.
The next thing that happens is that the little fish changes its way of
swimming. Hitherto it has driven itself through the water by means of
its tail; now it uses what were formerly its upper and lower fins, but
have now been turned into side fins. And by a very graceful waving
movement of these fins it winds its way, as it were, through the water.
But the third change is the strangest of the three. One of the eyes
would now seem to be useless, since it is on the lower surface of the
head as the fish lies on the sea-bottom, and would be completely buried
in the mud. But as soon as the fish goes and lies down at the bottom of
the sea, this eye actually begins to travel along the lower surface of
the head, till at last it works its way round and settles down by the
side of the other!
If you look at the flounders the next time you pass by a fish-market,
you will observe that both eyes are placed quite close together above
the same corner of the mouth. That is because the lower eye traveled
round the head till it found a resting-place by the side of the other.
In habits, all these fishes are very much alike. They are found in
almost all seas, except those of the polar regions, and in most parts of
the world are exceedingly plentiful, and everywhere form a cheap and
excellent food.
THE SWORDFISH
A very odd-looking creature is this. It abounds in the Atlantic and also
in the Mediterranean. Its chase affords one of the finest summer sports
to be enjoyed along the south coast of New England, where it is taken by
spearing from swift sailboats.
In this fish the upper jaw, which has hardly any teeth in it, is drawn
out into a long, slender, pointed beak. With this "sword" the
fish impales its victims, which are often of considerable size; but how
it gets them off its beak again in order to eat them nobody seems to
know.
This fish sometimes drives its way through the water with such
tremendous force that it has been known to pierce the planking of a boat
with its sword, which it had to snap short off in order to release
itself.
In the Natural History Museum at South Kensington, London, there is part
of a beam taken from the hull of a ship, into which one of these fishes
had driven its sword to a depth of twenty-two inches.
MACKEREL
One of the best known of all the salt-water fishes is the mackerel. This
fish lives in enormous shoals, which are always traveling from place to
place, and visit the same parts of our coasts at about the same season
in every year. Sometimes they are caught in most extraordinary numbers,
so that they can be purchased at very small prices. In some cases,
indeed, the catch has been so heavy that it has been found quite
impossible to draw in the nets, which had to be allowed to sink to the
bottom with the fishes still in them.
These nets are generally made with rather large meshes, not quite wide
enough to allow the fishes to swim through. When the mackerel are caught
they try to force their way through the meshes, but find that they
cannot do so. They then attempt to back out. In doing this, however, the
thin twine of which the net is made is almost sure to become entangled
with their gill-covers, so that they are held prisoners until the net is
lifted from the water.
When fully grown the mackerel is about sixteen inches long, and weighs
perhaps two pounds.
SUCKING-FISHES
Of the sucking-fishes, or remoras, there are about a dozen different
kinds, distinguished by the odd sucker-like disk on the upper
part of the head, by means of which they can attach themselves firmly to
any object to which they wish to cling. They often fasten themselves in
this manner to the hulls of ships, and also to the bodies of sharks and
the shells of turtles, and so are carried for long distances without any
exertion of their own.
So firmly do these odd little fishes cling, that it is most difficult to
remove them without injuring them, and the sharks and turtles have no
means of forcing them to loose their hold.
It is a very odd fact that the coloring of the sucking-fishes is just
the opposite of that which we find in almost all other fishes. Instead
of the upper surface being dark it is light, and instead of the lower
surface being light it is dark. But when one of these fishes is clinging
to a shark it is the lower surface which is seen, not the upper one; for
_that_ is pressed against the body of the shark; and in order to
prevent its enemies from seeing and eating it, the lower parts of its
body are colored just like the skin of the shark.
WEEVERS
Strange little fishes are the weevers, two kinds of which are found on
the coast of Europe.
Both are highly poisonous, a prick from the spines of the upper fin or
the gill-cover being almost as serious as the sting of a scorpion. The
poison lies in a deep double groove on each spine, and as the fishes
have a habit of burying themselves in the sand at the bottom of shallow
water, with only just the sharp spines projecting, they are rather apt
to be trodden upon by bathers.
Accordingly, when a fisherman catches a weever-fish he always cuts off
its back fin and the spines of its gill-covers at once; while in France
and Spain he is compelled to do so by law.
THE ANGLER
The angler, or all-mouth, is the name of a hideous creature--about five
feet long when fully grown--with a huge mouth, a great broad body shaped
very much like that of a seal, two big round eyes which look almost
straight up into the water above, and a row of long, slender
spines on the back instead of the usual fins. The first of these spines
has a broad, tufted, glittering tip, used for a most singular purpose.
It is a creature of prey, feeding entirely upon other fishes; and it has
a most enormous appetite, which is hardly ever satisfied. But, at the
same time, it is so slow in its movements that if it were to try to
chase its victims it would never get anything to eat. It seems to know
perfectly well, however, that fishes are very inquisitive creatures, and
that they are always greatly attracted by any object that glitters. So
when it feels hungry it lies down at the bottom of the sea, stirs the
mud gently up with its side fins, so as to conceal itself from view, and
dangles the glittering spine up and down in front of its open mouth.
Before very long some passing fish is sure to come swimming up to see
what this strange object can possibly be; and then the angler just gives
one snap with its great jaws, and that fish is seen no more.
Just to show you how successful it is in its fishing, we may tell you
that from the body of a single angler no less than seventy-five herrings
have been taken, while another had swallowed twenty-five flounders and a
John-dory!
There is another kind of angler which lives down at the bottom of the
deep sea, where it is always perfectly dark. There, of course, a
glittering spine would be useless, for the other fishes would not be
able to see it. So this angler has a spine which shines at the tip like
a firefly, so that it can be seen from a considerable distance as the
fish dangles it up and down!
GURNARDS
These, too, are remarkable fishes, having square heads, which look ever
so much too big for their bodies, and the first three rays of their
pectoral or breast fins made like fingers. These breast-fins are used
like fingers, too, for they serve as organs of touch, while the fish
also walks with them along the sand at the bottom of the sea.
At least forty different kinds of gurnards have been discovered, but
nearly all dwell along foreign coasts. The handsomest of these, perhaps,
is the red gurnard, which grows to a length of twelve or
fourteen inches, and is bright red above and silvery white below.
FLYING FISHES
Though objects of never-ending interest to every one who journeys
through the warmer seas, flying fishes do not really fly. They merely
skim for long distances through the air, just as the flying squirrel and
the flying dragon do; but instead of having a broad parachute-like
membrane to buoy them up, they are supported in the air by the pectoral
or breast fins, which are very large. These fins do not beat the air,
like the wings of a bird. They merely support the body. And the power of
the so-called flight is due to a stroke of the tail just as the fish
leaves the water.
The reason why these fishes take their long leaps through the air
appears to be that they are much persecuted by other fishes, bigger and
stronger than themselves, and that they know quite well that they will
be overtaken if they remain in the water. They do not usually rise to a
height of more than a few feet above the surface, and the greatest
distance to which they can travel without falling back into the water
seems to be about two hundred yards. Whether they can alter the
direction of their course while they are in the air is uncertain. Some
observers say that they can, while others declare that they cannot. But
it is possible that they may sometimes do so by just touching the crest
of a wave with their tails.
Flying fishes are found in all the warmer parts of the sea, and are very
common in the Mediterranean and the West Indies.
THE HERRING
Like the mackerel, the herring is one of those fishes which live in vast
shoals and are of great value as a cheap and nutritious food. These
shoals consist of millions upon millions of fishes, and when they are
swimming near the surface of the sea their presence can generally be
detected by the numbers of sea-birds which follow them and devour them
in countless thousands. Whales, too, often follow the shoal for
days together, and sharks and many other big fishes do the same. Yet
nothing seems to lessen their numbers.
These shoals generally appear in the same parts of the sea, year after
year, at the same season. But sometimes the herring will desert their
favorite haunts without any apparent cause. During spring and early
summer they remain in deep water; but in June and July they come in
nearer the coast in order to spawn.
GOBIES
There are still several very curious and interesting fishes about which
we should like to tell you; and among these are the gobies. Many
different kinds of these odd little creatures are found in different
parts of the world other than North America; but perhaps the best known
of all is the black goby, which is very common off British coasts. You
can often catch it by fishing with a small net in the pools which are
left among the rocks as the tide goes out. And if you look into these
pools from above, you may often see it clinging to the rocks round the
margin. It does this by means of the fins on the lower part of its body,
which are made in such a manner that when they are placed side by side
together they form a kind of sucker. And if you keep the fish in an
aquarium, it has an odd way of suddenly darting at the side of the tank,
clinging to it with its fins, and staring at you through the glass.
Some of the gobies make nests in which to bring up their little ones,
just as the sticklebacks do. One of them, the spotted goby, which is
found rather commonly in the lower reaches of the Thames, nearly always
takes one of the shells of a cockle for this purpose. First it turns the
shell upside down; then it scoops out the sand from beneath it, and
smears the surface of the hollow with slime from its own body; and then
it piles loose sand over the shell, so as to keep it in position.
Lastly, it makes a little tunnel by which to enter the nest from
outside. This work is always performed by the male. When the nest is
quite finished the female comes and lays her eggs in it, after
which the male keeps guard over them until they hatch, about eight or
nine days later.
MUD-SKIPPERS
More curious still are these fishes, which are found on the coasts of
the tropical seas, and often make their way for some little distance up
the estuaries of rivers. They have singular eyes, which are set on the
upper surface of the head, and can be poked out to some little distance
and drawn back again in the oddest way. And besides that, these eyes
have eyelids. Then the lower fins are made just like those of the
gobies, but with an even greater power of clinging, so that the fish can
climb by means of them. Often these queer little creatures leave the sea
altogether and skip about on the muddy shore, or even climb up the
trunks of the trees which overhang the water. Sometimes they will rest
for quite a long time on the spreading roots, snapping at the flies and
other small insects which come within reach. They do not look like
fishes at all as they do so. They look much more like rather big
tadpoles. And if they are suddenly startled they go hopping and skipping
back into the water, not diving at once, but leaping along over the
surface, very much as a flat stone does when thrown sideways from the
hand.
Some of these fishes were kept for some time at the London Zoo, and when
they were out of the water they had an odd way of lying at full length
and raising their heads and the front part of their bodies by means of
their lower fins, so that they reminded one very much of a man with his
elbows resting upon the table.
PIPE-FISHES
The pipe-fish has its mouth drawn out into a very long snout, so that it
forms a kind of tube; the body is sixteen or eighteen inches long, yet
scarcely stouter than an ordinary drawing-pencil; and the only fin,
besides a small one on the back, is a tiny one at the very tip of the
tail. Besides this, the whole head and body are covered with bony
plates, which form a kind of coat of mail. And the fish is even
odder in habits than in appearance, for when the eggs are laid they are
put into a pouch in the lower part of the body of the male, and are kept
there until they hatch! It is even said that after the little ones are
hatched and are able to swim about in the water, they will return into
the pouch of the parent in moments of danger, just as young kangaroos
will into that of their mother. But this does not seem to have been
proved.
Pipe-fishes are not uncommon on our coasts, and you may often find them
in the pools among the rocks when the tide is out. They swim half erect
in the water, and if you watch them carefully you may see them poking
their long snout-like mouths in among the seaweeds in search of food,
standing on their heads among the eel-grass, in which position they are
hard to see, or blowing furrows in the sand at the bottom of the pool in
order to turn out any small creatures which may be lying hidden in it.
THE SEA-HORSE
Closely related to the pipe-fish is the sea-horse, which reminds one of
the knight in a set of chessmen. It has a long and slender tail, which
is prehensile, like that of a spider-monkey; and by means of this organ
the fish anchors itself firmly down to the stems of seaweeds, or to any
small object which may be floating on the surface of the water.
The eyes of this fish can be moved independently of each other, like
those of a chameleon; and if you keep one of these creatures in a bowl
of sea-water and watch it for a few minutes, you will find it hard to
believe that it is not purposely "making faces" at you!
The male sea-horse, like the male pipe-fish, has a pouch underneath his
body, in which the eggs are placed as soon as they are laid, and are
kept until they hatch.
The sea-horse swims by means of a single fin on its back, which acts on
the water very much like the screw of a steamboat. Just at the back of
its head are two more fins, and when these are thrown forward they look
like the ears of a horse, increasing the queer resemblance of
its long head to that of a pony.
Sea-horses are found in most of the warmer seas, and in summer float
north with the Gulf Stream, so that they are frequently seen near New
England.
CONGERS
Just as there are eels which live in the fresh water, so there are eels
which live in the sea. These are known as congers, and very often they
grow to a great size. A conger eight feet long is by no means uncommon;
and a fish of this length will weigh at least one hundred pounds.
Congers generally live in rather shallow water off a rocky coast, where
there are plenty of nooks and crevices in which they can hide during the
daytime. It is rather curious to find that those which live in muddy
places are nearly always dark brown or black in color, while those which
lie upon sand are light-colored, and sometimes almost white.
These eels are generally caught by means of long lines, which are set at
intervals with short "snoods" just like those which are used in catching
cod. The hooks are generally baited with pilchards, or else with pieces
of the long arms of cuttles. When the congers are lifted on board the
scene is usually an exciting one, for they are very powerful and active,
and go twisting and writhing about in the most extraordinary manner,
slapping vigorously on all sides with their long tails. These tails,
too, to some extent, are prehensile, and sometimes the fishes will seize
the gunwale of the boat, and then, with a sudden effort, pull themselves
over the side and drop back into the water. As soon as they are lifted
on board, the fishermen always try to stun them by a heavy blow on the
lower side of the body, after which, of course, they can be easily
killed.
Congers feed, as a rule, upon mollusks, which we wrongly call
shell-fish, devouring them shells and all. They will also eat small
fishes, however, and sometimes they are cannibals; for inside the body
of one of these fishes a young conger was found that was three feet in
length!
AMPHIOXUS, OR LANCELET
In this we see a creature so curiously formed that a good many
naturalists have doubted whether it ought to be ranked among the fishes
at all. For in appearance it is much more like a slug; and it has no
skull, and no brain, and no bones, and no eyes, and no gills, and no
heart! It has a fin running along its back, however, and although it has
no spine, it possesses a spinal cord. So it is considered as the very
lowest of all the fishes, and as a kind of link between the animals with
bones and those without them.
This strange little creature is about two inches and a half long when
fully grown, and is so transparent that one can almost see through its
body. It is very active, and can wriggle and twist about in the water,
or on the mud, with considerable speed. It spends most of its life
concealed under large stones, or lying almost buried in the muddy sand
at the bottom of the sea. And it seems to feed upon those minute atoms
of decaying animal and vegetable matter which are always floating about
in countless millions in the waters of the sea.
INVERTEBRATES