Perches
Another very handsome fresh-water fish is the perch, which is plentiful in almost every river and lake in the warmer parts of the whole world. In color it is rich greenish brown above and yellowish white below, with from five to seven upright dark bands on either side of its body, while the upper fins are brown and the lower ones and the tail bright red.
The front fin on the back of the perch, which can be raised or lowered at will, is really a very formidable weapon, for it consists of a row of very sharp spines projecting for some little distance beyond the membrane which joins them together. Even the pike is afraid of these spines, and it is said that although he will seize any other fresh-water fish without a moment's hesitation, he will never venture to attack a perch.
Early in the month of May the mother perch lays her eggs, which she fastens in long bands to the leaves of water-plants. Their number is very great, over 280,000 having been taken from quite a small perch of only about half a pound in weight!
The climbing perch of India, notwithstanding its name, is not a true perch, but belongs to quite a different family. It is famous for its power of leaving the water and traveling for a considerable distance over dry land. It does this in the hot season if the stream in which it is living dries up; and if you were to live in certain parts of India you might perhaps meet quite a number of these fishes shuffling across the road by means of their lower fins, and making their way as fast as possible toward the nearest river!
But how do they manage to remain out of the water for so long?
Well, the fact is that fishes can live for a long time out of the water if their gills are kept moist. In some fishes, such as the herring, this is not possible, because their gills are made in such a way that they become dry almost immediately. But the climbing perch has a kind of cistern in its head, just above the gill-chambers, which contains quite a quantity of water. And while the fish is traveling over land this water passes down, drop by drop, to the gills, and keeps them constantly damp.
When this fish has been kept in an earthenware vessel, without any water at all, it has been known to live for nearly a week!
The Carp
Another fish which will live for quite a long time out of the water is the carp, which has often been conveyed for long distances packed in wet moss.
This fine fish is a native of the Old World, where it is found both in rivers and lakes, but prefers still waters with a soft muddy bottom, in which it can grovel with its snout in search of food. During the winter, too, it often buries itself completely in the mud, and there hibernates, remaining perfectly torpid until the return of warmer weather. It is not at all an easy fish to catch, for it is so wary that it will refuse to touch any bait in which it thinks that a hook may be concealed. And if the stream in which it is living is dragged with a net, it just burrows down into the mud at the bottom and allows the net to pass over it.
Owing to this crafty and cunning nature, the carp has often been called the fresh-water fox.
The carp is a very handsome fish, being olive brown above, with a tinge of gold, while the lower parts are yellowish white. It sometimes weighs as much as twenty-five pounds, and has been known to lay more than 700,000 eggs! It is domesticated in many parts of North America and other countries.
The Barbel
Found in many Old World rivers, the barbel may be known at once by the four long fleshy organs which hang down from the nose and the corners of the mouth. These organs are called barbules, and may possibly be of some help to the fish when it is grubbing in the soft mud in search of the small creatures upon which it feeds. It spends hours in doing this, and a hungry barbel is sometimes so much occupied in its task that a swimmer has dived down to the bottom of the river and caught it with his hands. From this curious way of feeding, and its great greediness, the barbel has sometimes been called the fresh-water pig.
In color this fish is greenish brown above, yellowish green on the sides of the body, and white underneath. When fully grown it weighs from ten to twelve pounds.
The Roach
This is one of the prettiest of the European fresh-water fishes, which is found in many lakes and streams. The upper part of the head and back are grayish green, with a kind of blue gloss, which gradually becomes paler on the sides till it passes into the silvery white of the lower surface. The fins and the tail are bright red.
The roach does not grow to a very great size, for it seldom weighs more than two pounds. It lives in large shoals, and in clear water several hundred may often be seen swimming about together.
The Pike
One of the largest and quite the fiercest of the British fresh-water fishes is the pike, which is found both in lakes and rivers. In America we have no pike proper, but in some of the great western lakes a very large relative of similar habits known as the maskinonge; and our pickerels are only small pikes. Wonderful tales are told of the ferocity of the pike. He does not seem to know what fear is, and his muscular power is so great, and the rows of teeth with which his jaws are furnished are so sharp and strong, that he is really a most formidable foe. All other fresh-water fishes are afraid of him, while he gobbles up water-birds of all kinds, and water-mice, and frogs, and even worms and insects. And no matter how much food he eats, he never seems to be satisfied.
When the pike is hungry, he generally hides under an overhanging bank, or among weeds, and there waits for his victims to pass by.
The young pike is generally known as the jack, and when only five inches long has been known to catch and devour a gudgeon almost as big as itself. With such a voracious appetite, it is not surprising that the fish grows very fast, and for a long time it increases in weight at the rate of about four pounds in every year. How long it continues to grow nobody quite knows; but pike of thirty-five or forty pounds have often been taken, and there have been records of examples even larger still.
In color the pike is olive brown, marked with green and yellow.
Trout
Perhaps the greatest favorite of all anglers is the trout, which, in one or more of its various species, is to be caught in almost every swift stream and highland lake throughout the temperate zone, except where the race has been destroyed by too persistent fishing. This happens everywhere near civilization, unless protective laws regulate the times and places where fishing may be done. Similar laws are required to save many other kinds of fishes from quick destruction at the hands of the thoughtless and selfish, and they should be honestly obeyed and supported in spite of their occasionally interfering with amusement.
Trout are graceful in form and richly colored, most of them having arrangements of bright spots and gaily tinted fins. The common trouts of Europe and the eastern half of the United States and Canada are much alike; but in the Rocky and other mountains of the western shore of our continent others quite different are scattered from the Plains to the Pacific. One of the most interesting and beautiful of these, the rainbow-trout, has been brought into the East, and has made itself at home in many lakes and rivers of the Northern States and Canada.
The trout is an extremely active fish, and when it is hooked it tries its very hardest to break away, dashing to and fro, leaping, twisting, and fighting, and often giving the angler a great deal of trouble before he can bring it in. In small streams it seldom grows to any great size, but in some of the Scottish lochs and lakes of Maine trout weighing fifteen or even twenty pounds are often taken. It is sometimes considered, however, that these belong to a different species.
The Salmon
More famous even than the trout is the salmon, the largest and finest of all our fresh-water fishes, which often reaches a weight of forty-five or fifty pounds, and sometimes grows to still greater size.
It is hardly correct, however, to speak of it as a fresh-water fish, for although salmon are nearly always caught in rivers, they spend a considerable part of their lives in the sea.
Salmon are of two kinds—the Atlantic and the Pacific species; and the life-history of each is a very curious one.
During the winter the parent fishes of the Atlantic salmon, which used to be exceedingly numerous in all our northern rivers emptying into the Atlantic, and still haunt the rivers of Northeastern Canada, and of Scotland, make their way as far up a clear and gravelly river as they possibly can, till they find a suitable place in which to lay their eggs. The mother then scoops a hole at the bottom of the stream, in which she deposits her eggs in batches, carefully covering up each batch as she does so. At this time both parents are in very poor condition, and the males are known to anglers as "kelts." For a time they remain in the river, feeding ravenously. Then in March or April they travel down the river and pass into the sea, where they stay for three or four months, after which they ascend the river again, as before.
Meanwhile the eggs remain buried in the gravel for about four months. At the end of that time the little fishes hatch out, and immediately hide themselves for about a fortnight under a rock or a large stone. You would never know what they were if you were to see them, for they look much more like tadpoles than fishes; and each has a little bag of nourishment underneath its body on which it lives. When this is exhausted they leave their retreat and feed upon small insects, growing very rapidly, until in about a month's time they are four inches long. They are now called parr and have a row of dark stripes upon their sides, and in this condition they remain for at least a year. Their color then changes, the stripes disappearing, and the whole body becoming covered with bright silvery scales.
The little fishes are now known as smolts, and, like their parents; they make their way down the river and pass into the sea. There they remain until the autumn, when they ascend the river again. By this time they have grown considerably, weighing perhaps five or six pounds, and are called grilse. And it is not until they have visited the sea again in the following year that they are termed salmon.
When salmon are ascending a river and come to a waterfall, they climb it by leaping into the air and so springing into the stream above the fall, trying over and over again until they succeed. When the fall is too high to be climbed in this way, the owners of the river often make a kind of water staircase by the side of it, so that the fishes can leap up one stair at a time. This is called a salmon-ladder.
North Pacific Salmon
Now this description would not at all fit the case of the salmon which live in the North Pacific and ascend the rivers of California, British Columbia, and Alaska, and of Siberia and Japan on the other side of the ocean. These are the salmon which supply the whole country, and many other countries, with their pink flesh, boiled, and sealed in cans, so that it may be sent long distances and kept many months without spoiling. Every spring and summer, at different times according to the locality and the species—there are five kinds of importance, caught for the trade—vast numbers of them enter the mouths of the rivers and begin to make their way up-stream in their effort to reach the shallow head waters of each river, and of every one of its tributaries. It is at this time that they are caught by spearing, netting, and various contrivances; but laws prevent any general obstruction which would altogether stop the advance of the host, so that while tens of thousands are taken great numbers escape and pass on, as it is necessary they should do in order to lay eggs and so keep up the race.
This takes place far up at the heads of the streams in the foothills of the mountains; and having deposited the spawn, late in summer, the spent fish begin to drift down stream again. But all this time they have been eating nothing, they are worn with the long struggle against the rapids, often wounded by sharp rocks, and are good for nothing to catch or eat. In fact, so fagged out and weak are they that all of them die before any reach the mouth of the river. It is a strange fact that of all the vast host of salmon which each summer climb the rivers not a single one gets back to the sea.
A year later, however, the young hatched from the eggs which were left behind them at the heads of the streams swim down the rivers and enter the ocean. There they remain, probably not very far from land, for two or three years, feeding and growing until they are of full size and strength; and each season a class of them, having reached the right age and condition to spawn, force their way up to the spawning-grounds, to leave their eggs and then die, as did their parents before them.
Eels
The only other fresh-water fishes which we can notice are the eels, which look more like snakes than fishes, for they have long slender bodies, with a pair of tiny fins just behind the head, a long one running along the back and tail, like a crest, and another, equally long, under the body. And they are clothed with a smooth, slimy skin instead of with scales.
These curious creatures live in ponds and even in ditches as well as in rivers, and are very plentiful in all parts of the northern hemisphere. During the daytime, although they will sometimes bask at the surface in the warm sunshine, they generally lie buried in the mud at the bottom of the water, coming out soon after sunset to feed. And when the weather is damp, so that their gills are kept moist as they wriggle through the herbage, they will often leave the water and travel for some little distance overland.
They frequently do this when they are traveling toward the sea. For it is a strange fact that, although they are fresh-water fishes, eels both begin and end their lives in the sea.
In the first place, the eggs are laid in the sea—generally quite close to the mouth of a river. When the little elvers, as the young eels are called, hatch out, they make their way up the river in immense shoals. In the English river Severn, for instance, several tons of elvers are often caught in a single day; and about thirty million elvers go to the ton! After being pressed into cakes and fried, these little creatures are used for food; but they are so rich that one cannot eat very many at once.
When they have traveled far enough up the river, most of the elvers which have escaped capture make their way to different streams and pools and ditches, and there remain until their growth is completed. They then begin to journey back to the sea, and when they reach it they lay eggs in their turn. After this, apparently, they die.
In the rivers of South America a most wonderful eel is found which has the power of killing its victims by means of an electric shock, wherefore it is called the electric eel. The electricity is produced and stored up in two large organs inside the body, but how it is discharged nobody knows. If the fish is touched it merely gives a slight shudder. But the shock is so severe that quite a large fish can be killed by it, while a man's arm would be numbed for a moment right up to the shoulder.
Lampreys
The lamprey, which is found plentifully in many northern rivers, is very much like an eel in appearance. But it has no side fins, and instead of possessing jaws, it has a round mouth used for sucking, and resembling that of a leech; and on either side of its neck it has a row of seven round holes, through which water passes to the breathing-organs.
Lampreys seem to spend the greater part of their lives in the sea, but always come up the rivers to spawn. They lay their eggs in a hollow in the bed of the stream, which they make by dragging away stone after stone till the hole is sufficiently deep. Very often a large number of lampreys combine for this purpose, and make quite a big hole, in which they all lay their eggs together.
The length of the lamprey is generally from fifteen to eighteen inches, and its color is olive brown.
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
We now come to the second of the two great divisions of the animal kingdom, namely, the invertebrates, which includes all those creatures which have no bones. This division in its turn consists of a good many classes, just as that of the vertebrates does; and among these is that of the insects, the peculiarity of which is that they must pass through three stages of development before they reach their perfect form, namely: first the egg; then the grub, or caterpillar; and then the chrysalis, or pupa.
You can easily tell an insect when you see it by remembering one or two simple rules.
In the first place, its body is always divided into three principal parts, which are known as the head; the thorax, or chest; and the hind body.
In the second place, it always has six legs. Spiders have eight legs. Centipedes and millepedes have many legs. But an insect never has more nor less than six. And each of these limbs is made up of a thigh, a lower leg, and a foot; while the foot itself has from two to five little joints, the last of which usually has a pair of tiny claws at the tip.
Besides these, there are several other ways in which insects differ from the rest of the vertebrates. We need only tell you about one of them, however, and that is that in some form or other they always have four wings. Sometimes, it is true, you cannot see these wings. That is because they are not developed and cannot be used for flying. But still they are there, and by means of the microscope it is almost always easy to detect them.
These wings, however, take all sorts of forms. The wings of a butterfly, for example, are very different from those of a beetle or a bee; and because of these differences in the wings, insects are divisible into several smaller groups, which we call orders.
Beetles
First comes the order of the beetles. These are called Coleoptera, or sheath-winged insects, because their front wings, instead of being formed for flight, are turned into horny or leathery sheaths, or elytra, which cover up and protect the lower pair while not in use.
At least 150,000 different kinds of beetles have already been discovered in various parts of the world, of which America possesses tens of thousands; and probably quite as many more remain to be distinguished. Of these we can only mention a few of the most interesting.
The tiger-beetles are so called because they are such fierce and voracious insects, spending most of their time in chasing and devouring other insects. The commonest of them is about half an inch long, and is bright green above and coppery below. You may often see it darting about in the hot sunshine, and if you try to catch it you will generally find that it flies away as quickly as a bluebottle.
Ground-beetles are common in gardens. One often seen is about an inch long, and is deep black in color, with a narrow band of violet running round the outer edge of its wing-cases. This, too, is a creature of prey. It cannot hurt you; but if you pick it up it will make your fingers smell very nasty. For it can pour out from its mouth a drop or two of a dark-brown liquid which has a horrible odor.
Then there are a good many beetles which live in streams and ponds, and are called water-beetles in consequence. They can swim and dive very well, and are also able to fly. Almost every night they go for long journeys through the air. And when they want to go back into the pond they hover above it for a moment, fold their wings, and drop into the water with a splash. Only sometimes they fly over the roof of a greenhouse, and mistake that for a pond; and then you can imagine the result!
The cocktails are beetles with short wing-cases and very long, slender bodies, which they carry turned up at the rear end. Some of them are quite large, like the ugly black "coach-horse," but many are very small. Indeed, most of the "flies" which get into one's eyes on warm sunny days in England are really tiny cocktail beetles, and the reason why they make one's eyes smart so dreadfully is that they pour out a little drop of an evil-smelling liquid from their mouths, just like the purple ground-beetle.
Scavengers
The burying-beetles are so called because they bury dead animals. Have you ever wondered why we so seldom find a dead mouse or a dead bird, although these creatures must die in thousands every day? One reason is that as soon as they are dead a couple of "scavengers" are almost sure to come and bury them. They are big black beetles, sometimes with two broad yellow stripes across their wing-cases, and they dig by means of their heads, scooping out the earth from under the carcass till it has sunk well below the surface of the ground. Then they lay their eggs in it, come up to the surface, shovel back the earth till the dead body is quite covered over, and then fly away. And when the eggs hatch, the little grubs which come out from them feed upon the carcass.
Among the largest beetles are those called stag-beetles because the jaws of the male look very much like the horns of a stag. Those of the female are much smaller, but are so sharp and strong that they can really give a rather severe bite. These occur in various parts of the world, and are fond of flying slowly about on a warm summer evening, generally about twenty or thirty feet from the ground.
The cockchafer is common everywhere in spring, and if you shake a young birch-tree, or a hazel-bush, three or four of the great clumsy insects will very likely come tumbling down. They are rather more than an inch long, very stoutly and heavily built, and are chestnut brown in color, while their bodies are drawn out into a kind of point behind. The grubs of these beetles live underground, and do a great deal of mischief in fields and gardens, for they feed upon the roots of the plants, and very soon kill them.
Dor-beetles, too, are very common everywhere. You may often see them flying round and round in great circles on warm summer evenings, making a loud humming noise as they do so. They often blunder in at open windows, attracted by the lamplight, and children are afraid of them, but they can do no harm. If you catch one you will find that it is nearly black. You will also see that its front legs are broad and strong, and that they are set with a row of stout horny teeth. With these legs the beetle digs, using them with such address that in the course of an hour or two it will sink a hole in the ground ten or twelve inches deep, in order to lay its eggs at the bottom.
The famous Scarabæus of Egypt, which in days of old some of the people of that country used to revere, because they thought it a symbol of immortality, is really a kind of dor-beetle.
Skipjacks and Glowworms
Skipjacks, too, are beetles. You may know them by their long, narrow, glossy bodies, and by the fact that the head is hidden under the thorax, so that you can hardly see it from above. One very odd thing about them is that they are constantly losing their footing and rolling over on their backs; and their bodies are so shiny, and their legs are so short, that when they do so they cannot get up again in the ordinary manner. But after lying still for a moment they arch themselves into the form of a bow, resting only upon their heads and the very tips of their tails, and suddenly spring into the air, making an odd clicking noise as they do so. And as they fall they turn half round, and so alight upon their feet. For this reason they are often known as click-beetles.
These insects are the parents of the well-known wireworms, which often do such mischief in our fields and gardens, living underground for three or even four years, and feeding upon the roots of the crops, and of such bushes as the currant.
Then the glowworm is a beetle. Perhaps you may have seen its little pale green lamp shining in the grass on a summer evening. The light comes from a liquid inside the hind part of the body, the skin of which is transparent, and forms a kind of window, so that it can shine through; and the insect has the power of turning on its light and shutting it off at will. The lamp of the female beetle is very much brighter than that of the male, and while the male has both wing-cases and wings, and can fly very well indeed, those of the female are so small that one can hardly see them. Indeed, she looks much more like a grub than a beetle.
Deathwatches and Oil-Beetles
Deathwatches are small brown beetles which burrow into dead wood and call to one another by tapping with their horny heads. You may often hear them if you happen to be lying awake at night in a room in which there is old woodwork; and in former days people were silly enough to think that when this sound was heard it was a sign that somebody in the house was going to die! That is why these beetles are called deathwatches. They are quite small, and are brown in color, with rather long feelers and legs.
Crawling on grassy banks in the warm sunshine on bright spring days, you may often see a number of oil-beetles. These are large bluish-black insects which have an odd habit, if you pick them up, of squeezing out little drops of a yellow oily liquid from the joints of their legs! This oil has a pungent smell, and no doubt prevents birds, etc., from eating them. You will notice that the female beetles have enormous hind bodies, which they can hardly drag along over the ground. This is because they contain such a very large number of eggs, thirty thousand often being laid by a single beetle. She places them in batches in holes in the ground, and very soon afterward they hatch, and odd-looking little grubs with six long legs come out of them. No sooner have they left the egg-shells than these tiny creatures hunt about for a flower with sweet juices, which is likely to be visited by a wild bee. When they find one, they climb up the stem and hide among the petals. Then, when the bee comes, they spring upon it and cling to its hairy body, and so are carried back to its nest, where they feed upon the food which the bee had stored up for its little ones.
Weevils and Other Beetles
A great many beetles have a long beak in front of the head, with the jaws at the very tip. These are called weevils, and many of them are very mischievous. Grain of various kinds, for example, is destroyed in enormous quantities by the wheat-weevil and the rice-weevil, while the nut-weevil is the cause of those "bad" nuts which no doubt most of you know only too well. The mother beetle bores a hole through the shell of the nut while it is small, and the little grub which hatches out from the egg she leaves inside it feeds upon the kernel, leaving nothing behind but a quantity of evil-tasting black dust.
One of the handsomest of European insects is the musk-beetle, which you may often find sunning itself on the trunks and leaves of willow-trees in England in July. Often you can smell it long before you find it, for it gives out a strong odor much like that of musk. This beetle is sometimes nearly an inch and a half long, with long legs and still longer waving black feelers. In color it is rich golden green with a tinge of copper. But if you put one of its wing-cases under the microscope, it looks like a piece of green velvet studded all over with diamonds, and rubies, and sapphires, and emeralds, and topazes, which seem to turn into one another with every change of light.
The grub of this beetle lives inside the trunks of dying willow-trees, and feeds upon the solid wood.
Then there are the turnip-fleas, little black beetles with a yellow stripe on each wing-case, which skip about just as fleas do, by means of their hind legs. They are only too common in turnip-fields, and often do most serious mischief, nibbling off the seed-leaves of the young plants as soon as they push their way above the surface of the ground, and so destroying the greater part or even the whole of the crop.
And, lastly, there are the ladybirds, common everywhere. But perhaps you did not know that they are among the most useful of insects. The fact is that both as grubs and as perfect insects they live upon the green blight, or greenfly, an aphis which is terribly mischievous in fields and gardens, and destroy it in thousands of thousands. Indeed, if it were not for ladybirds, and for one or two other insects which help them in their task, we should find it quite impossible to grow certain crops at all.