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two furmidable-looking pincers, and two well-protected pairs of frost, filling the mouth of the shell

, or protruding beyond it. The tail is not shaped like that of the common crab, neither is it fanlike, an in the lobster, but is unsymmetrical, and is furnished with homoks, which enable him to retain a good hold of the castle he has aajuired. When he outgrows his dwelling he leaves it and searches for another, thrusting the tail into it to try if it gives him the accommodation he wants and pleases his fancy. If it does, he taken ponnession.

The right to a tenement is, however, attended occasionally by a contest. For why ?

“ Because the good old rule
Sufficeth them, the simple plan
That those should take who have the power,
And those should keep who can.”

There is reason to believe that this struggle is not always limited to the houseless wanderer, who battles with a rival, or endeavours to dislodge him, but at times involves the death of the real owner, the mollusc by whom the shell was formed. Professor Bell says :

“ It is a question of some interest whether the hermit crab always chooses for its habitation a shell already empty, or whether it actually kills and devours the inhabitant of one that suits its size, and then takes possession of its violated home. The latter I believe to be true, in many if not in most cases ; certainly, howover, not in all, us we often find the hermit occupying an old and long-abandoned shell. But so much more generally is it found in fresh shells that it can scarcely be doubted, even on this ground alone, that it often obtains its habitation by violence. The fishermen on the coast are fully persuaded of this ; and an intelligent person of this class at Bognor, assured me that the fact has often been observed by himself and others. He stated that the aggressor seizes his victim—the whelk, for instance-immediately behini the head, and thus kills or disables it, then eats it, and finally creeps into and appropriates its vacant shell.”

In the literature connected with zoology we come at times izpen an instance of a fable being adopted as a fact ; and again toen the very reverse, the fact being rejected as a fable. Such wismile fate of the one just mentioned ; for so strange and murwelinis did it appear to the renowned Swammerdan, that ke ti it as false, and regarded the hertsit crab as the originai ati.lt

the shell. Let us profit by the errors as well as by the truthful labours of those who have gone before us, ever bearing in mind that “free and unprejudiced spirits will neither antiquate truth for the oldness of the notion, nor slight her for looking young, or bearing the face of novelty.”

Mention has already been made of a crab carrying on his back a host of minute zoophytes. The larger hermit crabs also carry animal life of other kinds upon their dwellings. Serpulce and other worms that live in tubes, there fix themselves; acorn-shells take up their resting-place, and spread out their curious castingnets to seize their prey. Sponges also select them, and occasionally, like other parasites, destroy their benefactors. On different occasions, however, I have dredged up a hermit crab, who seemed more happily circumstanced, for his companion was a very beautiful species of sea-anemone (Adamsia palliata). The late Rev. Dr. Landsborough refers to it in the following passage, which is taken from his Excursions to the Island of Arran :- .“ Many naturalists have observed that there seems to be a treaty of union betwixt the hermit crab and the spotted sea-anemone. On this occasion we found that the spotted anemone had fastened itself to the outer lip of many of the roaring buckies (Buccinum undatum) brought up by the dredge, and wherever there was an anemone without, there we found a hermit crab within. In all likelihood they in various ways aid each other. The hermit has strong claws, and while he is feasting on the food he has caught, many spare crumbs may fall to the share of his gentle-looking companion.

But soft and gentle-looking though the actinia be, she has a hundred hands, and woe to the wandering wight who comes within reach of one of them, for all the others are instantly brought to its aid, and the hermit may soon find that he is more than compensated for the crumbs that fell from his own booty." I cannot venture to add any surmise as to the proportionate gain of the bustling crab and his attractive partner, but I may mention à circumstance that occurred when death had dissolved their partnership. I had placed them in my glass tank with other marine creatures. The crab died. Next day we found that the anemone had forsaken the empty shell, and fixed herself elsewhere. She did not long survive ; nor were her beauties ever displayed as they had been while on the shell.

The hermit crab has been known to carry a heavier burden than the one just mentioned. One of them, of the largest species (Pagurus Bernhardus), was in a tank in the Royal Zoological Gardens at Dublin. In walking about with his capacious shell (Buccinum undatum), he happened to come close to one of the largest sea-anemones that live upon the shores (Actinia crassicomis). This creature would appear to have powers of discrimination beyond what is generally supposed, for it immediately seized the shell and fixed itself upon it. There it remained as immovable as the old man of the mountain on the back of Sinbad. In ordinary cases, the 'anemone draws back its feelers when they are touched. But now, when the crab rushed about, and knocked the anemone against various objects in his progress, these sensitive organs were never retracted ; the knocks were taken as things of course, and not allowed to interfere with the enjoyment of the ride on crab-back.

A native species of crab (Hyas araneus) has been known to bear a still heavier burden. The upper shell (carapace) of the crab was two inches and a quarter in length, and on it an oyster three inches in length had attached itself. On the oyster shell, which was apparently five or six years old, were many large acornshells (Balani), so that the crab, Atlas-like, must have borne a world of weight upon its shoulders. So long as a crab goes on increasing in size, its shell, as already mentioned, is cast off and renewed. But it had not been cast off since the time the oyster made good its settlement upon it. Hence the presence of this oyster affords interesting evidence that the hyas lived several years after attaining its full growth. Both crabs and oysters, though dead, were in a fresh state when brought to the naturalist, in whose cabinet they are now preserved.

Perhaps some of the active merry boys, by whom these pages are read, may be so fortunate as to add to our present knowledge such materials as may assist in determining the average longevity of some of our native crustacea,—what length of life in them would represent the “ three - score years and ten ” of human existence.

1 Thompson's Natural History of Ireland, vol ir.

SEA-A NEMONES.

“The living flower that rooted to the rock,

Late from the thinner element,
Shrunk down within its purple stern to sleep,

Now feels the water, and again
Awakening, blossoms out
All its green anther-necks."-SOUTHEY.

It was

1. SEA-SIDE EXCURSION.-I had brought with me to the country one of those tanks which are now sold in London for keeping aquatic animals and plants in a living state. about eighteen inches long, and nearly a foot deep. A little piece of rockwork had been made in the centre, and at each of the corners a stone had been placed on which was a sea-weed, whose dark-green stems reached nearly to the surface of the water. The slate-bottom of the tank was covered with roundish white pebbles. The glass sides were clean and bright, the sea-water was pure, and every now and then bubbles of oxygen gas were given out by the plants, and rose sparkling to the surface. The house was ready, but those who were to be its inmates had not yet arrived.

Resolved that it should not remain any longer unoccupied, I summoned three children, who, with great alacrity, got ready for a stroll upon the beach. We carried with us a basket containing some wide-mouthed glass vessels, a small spade, a stout knife, a tin box, and a can for sea-water. In ten minutes we stood among little ledges of rock, which were at low-water laid bare to our research. Some of them were clothed with the most common kinds of brown sea-weed, and among them were little sandy havens and rocky pools, each of which, like rival candidates for our favour, displayed attractions of its own.

The children set to work to collect for the tank. They wanted sea-anemones of every variety of colour, brown, yellow, olive, green, scarlet, and vermilion, for such, and so varied are the tints of the most common species (Actinia mesembryanthemum). While they are so employed, let me tell my young readers what is meant by a Sea-Anemone.

THE SEA-ANEMONE is a lowly member of the animal kingdom, and belongs to the class of Zoophytes or “plant-animals," a name which reminds us, that, in former times, they were supposed to occupy a place between animals on the one hand, and plants on the other. On the sides of the rocks, and under the sea-weed, about the base, are soft fleshy hemispherical bodies, of different tints, but mostly liver-coloured or brown. These are sea-anemones in their contracted state. To judge of what they are when expanded, look into that little rock-basin, and you will see half a dozen of them spread out as if they were the favoured flowers of a sea-maid's garden :

“The marigold that goes to bed with the sun

And with him rises weeping,” is not more beautiful. Stoop down and touch the expanded blossom. The moment that you do so its petals begin to close ; you find your finger is seized, and that it is held not by pressure only, but by some adhesive secretion. You cannot doubt that any small animal, a wandering crab, or a luckless shell-fish, would have no chance of escape, but would be consigned forthwith to the central mouth, which gives ready access to the capacious stomach beneath. I have given a sea-anemone for his dinner a cockle as large as himself. He contrived to swallow it entire, and next day rejected by the mouth the undigested remains of the shell. Another time I dropped a periwinkle 1 into the gaping mouth; in an hour or two afterwards, it was creeping about as usual : the sea-anemone had not chosen to eat. A friend informs me, he, in like manner, dropped in a small crab; next day he saw the crab walking about as usual, but wanting one of his legs. The anemone can bear long abstinence and changes of temperature. It can even bear removal from water for many successive hours. On one occasion, when I was writing, a child brought a sea-anemone in his hand to show to me. He left it in one of the divisions of the writing-desk without my knowledge. The desk was locked. On opening it on the third day afterwards the luckless sea-anemone was discovered, and being placed in a glass of sea-water, expanded itself as usual. But these grievances are trifling compared to some to which it is occasionally subjected, and which it survives. If cut down right in two, each part will reproduce what is deficient, and two anemones will result. If cut across, the upper part will continue to take food,

1 On both the Scotch and Irish coast, this is more commonly called “whelk."

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