Theodore Wood

“ IF you grope about in the dark nooks and corners of a rock-pool, quite close down to the water’s edge, when the tide is out, you may perhaps find a curious little creature which looks rather like a greyish-white cucumber, with an odd feathery tuft at one end of its body. ”

“ Remember, then, in the first place, that what we always call the “shell” of a crab is not really a shell at all. That is, it is not in the least like the shell of an oyster, or a periwinkle, or a cowry, or a whelk. In these creatures the shell grows together with the animal inside it, and is never thrown off all through their lives. But the “shell” of a crab never grows at all. It is really a kind of crust of lime on the outside of the skin, which will not even stretch in the very least degree. ”

“ If you examine the rocks which are left dry when the tide goes out, you will often find that they are covered almost all over with small shells which look rather like those of tiny limpets. Only at the top of each shell there is a little hole, from the margin of which a number of ridges run down to the bottom. And these ridges are so sharp, that if you happen to slip when you are wandering about among the pools, and catch at a rock to save yourself, they will cut your fingers almost as if they were knives. ”

“ The commonest of these odd little creatures, perhaps, is the Black Goby. But the Spotted Goby is very nearly as plentiful. It is rather hard to see, because it is coloured just like the sand at the bottom of the pool, on which it is very fond of resting. But if you scoop out the water from a shallow pool you will often find, not only the goby, but its nest as well. For this little fish makes a most curious nest in which to place its eggs. First of all it hunts about till it has found half an empty cockle-shell, lying at the bottom of the water with its hollow side downwards. ”

“ And when their bodies are quite filled with sand, they come up to the entrances of their burrows and pour it out in the little twisty coils which everybody who has walked on the shore knows so well by sight. ”

“ Indeed, I do not think that a crab can hear sounds in the air at all. But water carries sounds much more readily than air does, so that if you were to dive into a lake, or into the sea, on a calm, still day you could easily hear the beat of the oars in a boat half a mile away. And the ears of the crab are made in such a way that they can hear sounds in the water quite well, even though they may be deaf to sounds in the air. ”

“ On any muddy stretch of beach, when the tide is out, you may see numbers and numbers of little twisted casts, just like those which you may find on the lawn in the garden on any warm damp morning. These are made by Lug Worms, or “logs,” as the fishermen generally call them, and they really consist of sand which the worm has swallowed during the last three or four hours. For lug worms burrow by swallowing mouthful after mouthful of sand, until they can swallow no more. They eat their way down into the sand, in fact, just as earth-worms eat their way down into the ground. ”

“ So a sea urchin is able to move its spines about quite freely. Indeed, it sometimes walks with them as well as with the little sucker-feet, which it pokes out through tiny holes in the shell just as a starfish does, moving a few forward at a time, and so hitching [112] its way along over the sand at the bottom of the sea.
If you succeed in finding a live sea urchin—and you can generally do so without very much trouble, by hunting in the pools among the rocks when the tide is out—you will notice that it has a very big mouth, with five perfectly enormous teeth. ”

“ WE now come to the Molluscs, or Soft-bodied Animals, of which there are a very great many. Some of them live in shells, like the oyster and the whelk, and are often spoken of as “shell-fishes.” But they are not really fishes at all, for they have no bones as fishes have, and are made in quite a different way. And there are just a few of them which have no shells at all.
One of these is that very curious creature which we call the Cuttle. You may sometimes find it in the rock-pools, lurking in the crevices among the rocks, or hiding under the masses of sea-weeds which grow round the edges. ”

“ If you look on the upper part of the shell, you will see that a pale streak runs across it from one side to the other. This streak marks the line where the edges of the two sides of the body almost meet.
In some parts of the world cowry shells are used instead of money. It seems rather an easy way of getting rich, doesn’t it, just to go and pick up shells on the sea-shore? But then fifteen hundred of these cowries are only worth about a shilling, so that you would have to pick up a very great many even if you only wanted to do a day’s shopping! ”

“ The fish is always very careful indeed to conceal itself, for even when the sea-bottom is sandy it does not lie upon the surface, but wriggles its way right down into the sand, only leaving just its eyes and a small part of its head above it.
You can always tell a plaice when you see it by the bright reddish-yellow spots upon the upper side of its body and its fins. And besides these, it always has a row of little bony knobs on the upper side of its head. You can catch it just as you can catch flounders, by paddling in the sea. ”

“ Then if you look at the first joint of the greater feelers through the microscope, you will see two other tiny glands. These are the crab’s noses, by which it can smell odours in the water just as we can smell odours in the air. It always seems to find its food by scent, and if one of those basket-like traps which we call crab-pots is baited with a few pieces of decaying fish and lowered into the sea, crabs will smell the bait from quite a long distance away, and come hurrying up to obtain a share in the banquet. ”

“ The crab benefits, because no fish will ever touch him so long as an anemone is attached to his whelk-shell. There are plenty of fishes which would be quite ready to gobble him up, whelk-shell and all, if it were not for this creature. But fishes know quite [80] well that sea anemones can sting, and therefore never think of devouring them, no matter how hungry they may be; so that so long as an anemone is guarding the whelk-shell in which he lives, the hermit knows that he is perfectly safe. And the anemone benefits, because it gets a share of the crab’s meals. ”

“ What it does there nobody seems quite to know. It does not appear to injure the animal to whom the shell belongs, although it is very fond of the flesh of mussels, and if it finds one of those creatures lying dead will certainly devour it. Perhaps it only creeps inside its shell for the sake of safety. At any rate, it is a very timid little crab, and if you open a mussel and find a pea crab lying hidden inside it, it will tuck up all its legs quite close to its little round body and lie perfectly still for several minutes in the hope that you will think that it is dead. ”

“ The bird’s-foot starfish is not very often seen, for it lives some little way below low-water mark. But sometimes, when there has been a violent storm at a season of spring-tide—and you will remember that spring-tides come whenever there is a new moon or a full moon—it is flung upon the beach by the retreating waves, and you may find it lying on the sand when the tide is out. ”

“ Indeed, they will go without any food at all for three or four months together, and seem all the better for their long fast. But if you put a tiny dead crab, or a shrimp, or a sandhopper, into the midst of their spreading arms, you will see the tentacles close round it, and push it down into the mouth, which lies just in the very middle. For about forty-eight hours the animal will then remain closed up. But as soon as it has digested its dinner out will come the tentacles again, bringing with them the empty shell of the victim. ”

“ Sometimes people think that the reason of this is that at some previous time the animal had lost one of his claws through some accident, and was growing a new one, and that the new limb had not yet had time to reach its full size. However, this is not the case, for one claw of a lobster is always a good deal bigger than the other; and the real reason is that the two claws are used for different purposes. The larger claw is a weapon, with which the animal [82] fights, while the smaller one is an anchor, with which he clings to the weeds which grow on the rocks at the bottom of the sea. ”

“ Now when a lobster swims he just stretches his body straight out, and then doubles it suddenly up. As he does so the plates of the tail spread out, and form a kind of very broad and powerful oar, which strikes the water with such force as to drive the animal swiftly backwards. With a single stroke of its tail, indeed, a lobster can dart to a distance of forty or fifty feet, and that so quickly that even the swiftest fishes could scarcely overtake him. ”

“ You would think, perhaps, that when a lug worm bores its way through the loose sand, the sides of its burrow would fall in behind it as fast as it passed along. But from the surface of its body it pours out a thin, sticky liquid which binds the sand together, and forms a kind of lining to the burrow, like the brickwork of a railway tunnel. The burrow is generally about two feet deep, and the worm always lives in it with its head downwards. The worm itself, when fully grown, is from six to ten inches long. ”

“ So once in every year, until it reaches its full size, every crab has to cast off its shelly covering and get a new one in its place. A few days before the change takes place it always goes and hides away in some dark crevice among the rocks, or behind an overhanging mass of sea-weed, where none of its many enemies are likely to find it. It knows perfectly well, you see, that while it is without its coat of mail it will be quite helpless; for its claws will be so soft that it will not be able to use them, while its body will be quite unprotected. ”

“ Running round the oval body of the sea acorn are eight narrow bands, and on each of these are a number of very tiny scales, placed one above another, which keep on rising and falling again, like so many little trap-doors. ”

“ We call these crab caterpillars “zoeas,” and they are not in the least like their parents. There are a great many different kinds, of course, for every crab has its own zoea, just as every butterfly and moth has its own caterpillar, and some of them are not very much like some of the others. But they are always very tiny indeed—they are scarcely as large, in fact, as the smallest grains of sand—and they always have a very long curved horn in front of the body and another one behind, and long waggly tails. ”

“ People sometimes say that the curious substance which we call “coral” is made by “coral insects.” But the little animals which make it are not related in any way to the true insects. They are really tiny polyps, very much like those of the sea finger; and they suck up lime out of the water, and build it up underneath and round their own bodies, just as the madrepores do.
If you were to place one of these tuft corals in a vessel of clear sea-water, and to watch it carefully, you would soon see the little polyps poking themselves out, and spreading their tiny fleshy feelers, or “tentacles.” ”

“ These zoeas are very useful little creatures, because they feed upon the tiny scraps of decaying matter which are always floating about in the sea, and so help to keep the water always pure. They belong, in fact, to the great army of what I always like to call “nature’s dustmen”—those little animals whose duty it is to clear away the rubbish from the world. ”

“ It is generally about four or five inches in length and half-an-inch in width, and the object which looks so like a key-hole consists of its siphon tubes, the tips of which rest just above the surface of the sand when it is lying at the mouth of its burrow. It digs by means of its strong, fleshy “foot,” just as the cockle does, and its burrow, which goes straight downwards just like a well, is often as much as two feet deep. So it is not a very easy thing to get a razor out of its tunnel. ”

“ SEA ANEMONES HOW SEA ANEMONES ARE FORMED THE most beautiful of all the creatures which live in the sea are undoubtedly the Sea Anemones, which are just like living flowers of all sorts of lovely colours. ”

“ Something like a third part of its flesh turns into water! If you were to catch the animal at this time and to shake it, you would be able to hear the water swishing about inside its shell! Then it gets very restless indeed, and begins to wriggle about a good deal, turning and twisting from side to side, and rubbing its legs against one another, till it is quite tired out. ”

“ A good many different kinds of worms live on the sea-shore, and one of the most curious of these is the Sabella. For it lives in long, narrow tubes made of tiny grains of sand, which it sticks together with a kind of natural glue. You may find these tubes in great numbers just about low-water mark, and hundreds and hundreds of them are often twisted up together in great masses, which are sometimes several feet in diameter. The worms can travel up and down these tubes by means of tufts of stiff little bristles on each side of their bodies ”