In the Blenny family we find big, ugly fish as well as pretty little ones of strange shapes and lovely colours. There are several kinds of small Blennies in our rock-pools. The Eyed Blenny, or b.u.t.terfly Blenny is not very common along our sh.o.r.es, but may be seen now and again. It is only a few inches in length, with eyes like jewels, a kind of tuft over each eye, and a pretty spot on its tall back fin.
It will live quite well in a gla.s.s tank of sea-water; someone who kept many interesting fish says of this Blenny:--
"Our little b.u.t.terfly Blenny was not often to be seen. It was using an old whelk sh.e.l.l for a nursery. In this broken old sh.e.l.l the dainty fish was able to hide, and was so nervous that we seldom saw it. But we placed some food near the hole in the sh.e.l.l, and were rewarded by the sight of the b.u.t.terfly"s head, and its lovely eyes, each with a little movable ta.s.sel above it."
[Ill.u.s.tration: A SMOOTH BLENNY]
Hidden under weed and stones is another small brownish fish of the sh.o.r.e, the Gunnell or b.u.t.ter-fish. You may turn it out of its snug hiding-place, but you will have a hard task to catch it, even in a small rock-pool, and, once caught, it slips through your fingers like an eel.
Its body is eel-shaped, with a narrow fin on the back, and covered with a layer of slime. It well deserves the name of b.u.t.ter-fish.
The eggs of this strange little fish are rolled into a ma.s.s by the two parents. By curling their long, slimy bodies around the eggs, a closely-packed ball is the result. This precious ball of eggs is then taken care of, and guarded by the two fish. In this nursery both the father and mother fish take their share as guardians.
EXERCISES
1. Name three rock-pool fish. 2. Describe the Pipe-fish. 3. How does the Sand Goby anchor itself? 4. In what ways are these rock-pool fish so well fitted to live in such places?
LESSON X
SOME CURIOUS FISHES
Now and again that queer fish called the Sea-horse is found by our coast; a little brown fish, with bluish-white spots and lines on the sides and tail. But Sea-horses are common in warmer seas, in the banks of seaweed where they love to dwell. You would never guess that these curious creatures were fish.
The shape of the head, and the curved neck, remind you of a horse. It is also rather like the knight of the chess-board; or it may make you think of the dragon of the fable; but, really, the Sea-horse is like nothing on the earth, or in the waters. Nature has given it a special pattern of its own.
Sea-horses use their twisty tails as monkeys do, clinging to the seaweed with them. They swim along slowly, in an upright position. Every now and then they seem to be falling forward on their noses, and pull themselves up again, only to begin falling a moment after. It is fun to see them play hide-and-seek among the weed in an aquarium. Some Sea-horses are like floating sc.r.a.ps of torn weed; this, of course, hides them from the eyes of enemies.
[Ill.u.s.tration: SEA-HORSES]
They have no teeth, but a long mouth like a pipe; so you can be sure they eat only the smallest sea-creatures. To add to his odd look, the Seahorse moves his eyes in a comic fashion. One eye may roll round and look at you, while the other gazes forward.
As if this were not strange enough, he surprises us again. Mr. Sea-horse turns himself into a living nursery. He carries the eggs about with him, in a special pouch of skin! You will remember that the Pipe-fish also carries the eggs in his pocket, as it were. So you will not be surprised to hear that these two quaint fish belong to the same family.
We will leave the funny little Sea-horse, and look at a very different fish--the Sunfish. This remarkable fish often reaches a good size; even near our coast big ones are caught now and again, and in warmer seas, where they are often killed for the sake of the oil they contain, big fellows of half a ton are quite common.
This Sunfish has a peculiar shape. It looks as if it had once been an immense fish of the usual fish shape, but someone cut off the head and shoulders, and placed a short fin where the rest of the body had been.
Above and below there is a long pointed fin. The mouth is very small, and has no real teeth; so the Sunfish lives on small prey, such as the young of other fish, or small sh.e.l.l-fish.
Far away from land these strange Sunfish are met with, asleep near the surface, with the back fin showing above water. They roll along lazily, not unlike big cart-wheels. The top and bottom fins are for balancing and guiding the body, which is moved forward by the fin which frills the back part of this odd fish.
[Ill.u.s.tration: GLOBE FISH]
In the fishmonger"s shop you may sometimes see that ugly monster of the deep, the Angler-fish, or Fishing-frog. Now and again he finds his way into the fishermen"s nets; and is also caught on the lines, for he is so greedy that he will snap at a hooked fish. Rather than let go of his prey, he will be drawn to the surface. Then he is knocked on the head, and thrown into the boat with the other fish.
Being slow and clumsy, the Angler-fish cannot chase his prey, so gets his dinner by fraud. Nature has given him a fishing line and a bait! He has long spines on his head, so beautifully joined to the bones of the head that they can wave to and fro very easily. At the tip of the front spine there is a loose, shining strip of skin--that is the bait. Now, all anglers know how a fish is lured by a shining bait. The Angler-fish seems to know this too. He buries himself in the wet mud and sand at the bottom of the sea. Then he waves the long spine, so that the shining tip glistens as it shakes in the water, until a fish swims up to see what it is all about. A sudden snap, and that inquisitive fish is inside a huge, toad-like mouth, well furnished with rows of sharp teeth. The Angler-fish puts his catch in his pocket, and begins fishing again, for he is never satisfied. His pocket is a loose bag of skin in the throat.
This bag is always examined by fishermen who capture the Angler, for it may contain a nice big Plaice or Sole, worth money in the market.
There are Angler-fishes in every ocean, and some live in the very deepest parts. In those black depths the little waving "bait" would not be seen. So it is made to shine, like a bluish spark moving to and fro over the cold black slime of the sea-bed.
Down in those awful deeps it is for ever dark, and freezing cold, There is no day or night, summer or winter. No plants can live there. Yet in that strange, still world there are numbers of living things, though we know very little about them. There are weird Crabs, blind Lobsters, and fish terrors such as are never seen elsewhere.
In that darkness you would think that eyes would be of no use, but some of the deep-sea fish have great black owl-like eyes. Others are quite blind, or have eyes like pin-points. Some of them make their own light, glowing with rows of little lamps on their bodies, each like the lamp of the glow-worm of our country lanes. Blue, red, and green these lights are, but no one can tell you their real use, or why they are so coloured. The blind fish feel their way with long feelers, stretched out like the threads of a web.
[Ill.u.s.tration: THE FISHING FROG.]
As there are no plants down there, these strange fish must live mostly on one another! And here is a puzzle, for some of them have great big bodies, but small heads and tiny mouths; others have bodies like ribbons, but large heads and huge mouths, and some are such gluttons that they swallow fish twice their own size! This sounds absurd, but it is true. Their mouths gape open like trap-doors, and their stomachs are made to stretch, to hold their huge meals! There are other terrors of the deep with such big teeth that they cannot shut their mouths. No doubt the sea holds yet other weird fish which no man has seen.
EXERCISES
1. In what ways is the Sea-horse so different from most other fish? 2.
In what ways are the Sea-horse and Pipe-fish alike? 3. How does the Angler-fish catch its prey? 4. Mention a few strange facts about the deep-sea fish.
LESSON XI
THE GARDEN OF THE SEA
For many centuries men were puzzled over those strange growths in the sea--Corals and Sponges. Were they to be cla.s.sed as animals or as vegetables? It was by no means an easy question to answer.
Corals, with their pretty colour, and their stems and branches growing up from the sea-bed, were said to be shrubs, but they were as hard as rock, said some people, so how could they be vegetables? The reply to this was, that the Coral became hard as soon as it reached the air.
Then, of course, it was found that Coral was as hard under water as above it, and the question was still unanswered.
Sponges, too, were thought to be sea-plants for many, many years; though some people even said that they must really be made of hardened sea-foam! The Sponge took its place in the vegetable kingdom, then it was moved to the animal kingdom, and back again.
This went on for long years. Then, by careful watching, it was found that the Sponge is an animal. True, it is a very lowly member of the great kingdom of animals, yet it is one, and not a plant.
Like all other animals, the Sponge animal must eat, and its way of doing so is rather strange. If you look at any ordinary washing-sponge, you notice a great many very small openings and some larger ones amongst them. It is through the smaller holes, or pores, that the Sponge gets its supply of food. When it is alive, and in its own home, there is a current of water always pa.s.sing through its and the Sponge depends on the food which the water brings. Now, if you could watch this water-current, you would see that it rushes into some of the holes, and out of others; it has a certain path to follow. It enters the small pores, or openings, of the Sponge, and goes along narrow ca.n.a.ls, and is then led into larger ones. Finally, it rushes out again through those large openings we noticed. We may compare it with traffic coming into a city by many narrow streets, then pa.s.sing into broader roads, and at last out again by big main roads.
[Ill.u.s.tration: CUPS AND SOLID SPONGES]
[Ill.u.s.tration: _Photo: A. F. Dauncey_. SEA FURZE]
How does the Sponge animal cause this current; and how is it made to follow a certain path?
The narrow ca.n.a.ls in the Sponge are lined with lashes, or tiny hairs, so very small that you can just see them through a microscope. Now the secret of the wonderful water-current is a secret no longer. As long as the Sponge lives, these little lashes are always moving, always lashing the water along in one direction. They cause it to follow its proper course, through and through the Sponge, and out again into the sea. On its way it loses the tiny sc.r.a.ps of food which it contains, and carries away any waste stuff out of the Sponge.
You will have noticed that there are various kinds of Sponges in the market; some are large and flat, others small and cup-shaped; some are soft, and others rather hard. They are all somewhat h.o.r.n.y and elastic.
This "spongy" material is the skeleton of the Sponge animal, cleaned and dried for your use. Some kinds of Sponge would tear your skin if you tried to use them, for they have a hard skeleton. It is made of lime, and sometimes of flint, which the Sponge obtains from its food. Of course we use only those sponge-skeletons which are soft; but the cheaper kinds do often contain little flinty needles.
The best washing-sponges live in warm seas, attached to the rocks on the sea-bed. Divers go down and obtain them; or else they are dredged up, cleaned, dried, and sorted, and then sent to the market. Some Sponges, called Slime Sponges, have no skeleton, being merely a living ma.s.s of slime.
Coral is also the hard skeleton of a little animal, known as the Coral Polyp. The rest of the polyp"s body is soft jelly, which many fish regard as good food. The Sea Anemone--another jelly-animal--is first cousin to the Coral Polyp. And we may call the Jellyfish second cousin to these two, for it is in the same big division of the animal kingdom.
The pretty red Coral, then, is really the hard part of a little jelly-animal. This animal is much like a Sea-anemone, with a hard skeleton of lime. Coral, as you know, looks like a solid rock; it is really made of needles of lime, fastened together into a solid ma.s.s by the little Coral Polyp.