Hermit crab

“ The consequence is that the hermit crab always has to take the very greatest care of his tail. He is so dreadfully afraid that one of his many enemies will come up behind and give it a nip when he isn’t looking! So he protects it by tucking it away into the empty shell of a whelk. He never leaves this shell, but drags it about with him wherever he goes. ”

“ But they do not seem to mind being lonesome. They are great cowards, and think if they can but protect their lives there is nothing else to care for. Unlike the jolly crabs we have just left, the hermits are cross and unsociable."
"Oh, keep quiet and go away!" said one of the hermit crabs in a grumpy voice. "No one wants mermaids around here." Then every crab withdrew its head into its shell, and our friends saw them no more.
"They're not very polite," observed Trot, following the mermaid as Merla swam upward into the middle water. ”

“ HERMIT-CRAB AND CLOAKLET.
Every one is familiar with that impudent and intrusive species of Hermit-crab, [119] which, with its foxy-brown head and legs protruding, rolls over shells and pebbles with rattling patter, on almost every beach. The species I speak of is quite distinct from that homely and amusing subject. Though attaining a size fully equal, its proportions are much slenderer and more elegant; and the colours,—a light fawn, set off with soft tints of azure, lilac, and scarlet,—are far more beautiful than those of its fellow ”

“ Over by that rock a hermit crab has taken possession of a sea snail's shell, and set up housekeeping; with body partly hidden he waves his long bony tentacles, while his beady eyes stare at us from the doorway of his home. ”

“ One might suppose the hermit crab the least social of living tilings, but in reality he is gregarious and seems to enjoy the company of his friends. They wander in little bands; very often one finds two or three small ones perched on the back of a larger comrade and enjoying an effortless trip across the beach to the lagoon. ”

“ We have little more to say of the crustacea that go scrambling about, yet it would be impossible to overlook that peripatetic whelk-shell, which climbs about the stones with such marvellous activity. On a narrower inspection we perceive that it moves by a foreign agency. Those sprawling legs protruding from its mouth discover the hermit crab, which is obliged to dress its soft body in the first defensible armour it can pick up. A deserted whelk or common spiral shell is its favourite resort, but, like many bipeds, it has a love of changing its house ”

“ The internal dweller in the front parlour is the Hermit Crab (Paguras Prideauxii) , a creature seldom contented with its own pretty solid habitation, but ever seeking some further protection, which it generally finds in an empty Whelk-shell. ”

“ If we place a homeless hermit crab in a rock pool, the behaviour of the creature immediately suggests a feeling of uneasiness—a sense of danger—for it moves about in a very erratic fashion that is quite different from the straightforward and deliberate action of the same animal when properly protected; and very amusing results may be obtained by making it the subject of a few harmless experiments. For instance, drop down before it an empty whelk-shell that is much too large to properly accommodate its body. ”

“ It is called the hermit-crab, or Pagurus, by the systematists,Fig. 4. The most common species on the Atlantic coast is the little hermit—Pagurus longicarpus. A pair of nippers at the extremity of the tail, or naked abdomen, enables it to grip the columella, or upper part of the inside of the shell that it occupies, thus keeping itself snugly in place. As the crab increases in size by growth, it has to change its home for one more roomy; and this leads to some remarkable exhibitions of its instincts. The sight, which we have often beheld, is one of exciting interest. ”

“ Many species of hermit-crab frequently carry a large sea-anemone about with them on the mollusc shell which they use as a protecting-house; indeed, two or three of these beautiful many-tentacled polyps are often attached to them, and this is not at all a matter of chance, but depends upon instinct on the part of both animals; they have the feeling of belonging to each other. If the sea-anemone be taken away from the hermit-crab and put in a distant part of the aquarium, the crab seeks about till it finds it, then seizes it with its claws and sets it on its house again. ”

“ The Hermit-Crab always takes possession of the shell of some turbinated Univalve as its domicile. These are easily preserved by pulling out the animal after it is dead. An incision is made in the soft tail of the animal, and the contents allowed to run off; it is then filled with cotton and imbued with the preservative; some cement is then put on the tail and the animal returned to its shell, which completes the operation of preserving.
In sending home crustaceous animals, the larger species should be emptied of their fleshy matter, which, however, is not necessary with the smaller species ”

“ I have many times found Hermit-crabs out of their Shells in the mingled mass of a dredge-haul, and on three occasions have watched the method in which the houseless creature domiciliates himself. These were the only occasions on which I endeavoured to observe the operation: they always seem willing enough to exhibit their housing performance.
My plan of observation was simply this:—I put a naked crab into a large glass jar of sea water with one shell, the latter of size about proportioned to the former; and then I contemplated. In each case the crab proceeded in the same way. ”

“ A number of other animals are found associated with Hermit Crabs, without, as far as we can see, rendering any service in return for the house-room. The Whelk-shells inhabited by Eupagurus bernhardus (see Plate VII.) often contain one of the bristle-footed [215] worms (Nereilepas fucata) , which may sometimes be observed to protrude its head from the shell when the Crab is feeding, and to snatch away fragments of the prey from the very jaws of its host. It is thus, in the strict sense of the word, a commensal. ”

“ In tropical countries certain Hermit Crabs (Cœnobitidæ) have become adapted to a life on land, and one of these, the well-known Coconut Crab, or Robber Crab (Birgus latro) , which is the largest species of the tribe, has given up the habit of protecting itself with a shell, and its abdomen has again acquired a strong armour on the upper side. The marine Lithodidæ—to which the British Stone [62] Crab, Lithodes maia (Plate VIII.) belongs—seem at first sight to have little resemblance to the Hermit Crabs, for they have the abdomen very small, and tucked up under the body as in the true Crabs. ”

“ No doubt other species remain to be discovered, especially in the Upper and Middle Devonian.
Habits of Hermit-Crabs.—In the American Journal of Science for October, Mr. A. Agassiz records some observations on the hermit-crab. He raised a number of these animals from a very early stage in their life till they reached the condition in which they require the protection of a shell. A number of shells, some empty, others occupied by living mollusks, were now placed in the glass dish with the young crabs. ”

“ These sand-mullet are very dainty-feeding fish. They are particularly fond of the soft tail part of the hermit crabs which abound all over the island, especially after rain has fallen. Some of the shells (T. niloticus) in which they live are so thick and strong, however, that it requires two heavy stones to crush them sufficiently to take out the crab, the upper part of whose body is useless for bait. For a stick of tobacco, the native children would fill me a quart measure, and perhaps add some few shrimps as well, or half a dozen large sea urchins—a very acceptable bait for mullet. ”

“ That the anemone establishes itself on the shell, not by mere chance, as might sometimes happen, did the crab allow of it, may be demonstrated in a very delightful way; for if, when it is attached to a stone, a hermit-crab should be placed in its vicinity, it will, after a time, abandon its post, and gliding, like a snail, to the hospitable portals of its friend’s domain, proceed to attach itself there, much to the satisfaction of the latter. ”

“ All along the Bay of Tajourah the small hermit crab abounds, and formed, I should suppose, from what I saw, the principal prey of these birds. It would be a difficult thing to get at this kind of Crustacea, with all the means that seagulls 95can command; but instinct has taught them to have recourse to a method of unshelling the crabs that certainly I should not have thought of. Seizing the one they intend to operate upon, they fly up to the height of ten or twelve feet, and letting it drop it naturally falls on the heaviest, or topside of the shell. ”

“ Yet in no single instance have I witnessed a small crab sacrificed to the gluttony of a small anemone.
With regard to A. mesembryanthemum, A. bellis, and A. dianthus, they get so accustomed to the presence of their crusty neighbours, as not to retract their expanded tentacula when a hermit crab, for instance, drags his lumbering mansion across, or a fiddler crab steps through the delicate rays, like a sky terrier prancing over a bed of tulips.
Thus much I have felt myself called upon to say in defence of certain species of Actiniæ ”

“ There must be several varieties of hermit crab—I have counted three already: the ordinary small brown one called kakara, the huge red one found in deep water, and the black, hairy kind, whose pounded-up body is mixed with grated coconut to extract the oil. This latter is called unga; in the old days the lowest class of Rarotonga society was known by the same name—meaning, I suppose, that all of their property could be carried on their backs. The common variety is a good deal like the robber crab in habits ”

“ This would be disagreeable and inconvenient to the anemone, so it prefers a dead shell which has been taken possession of by a hermit-crab, and henceforth travels about with the crab. We would scarcely look for affection in a crab, but it has been said that the hermit grows fond of its companion, and that when it has outgrown its shell and has selected a new one, it will carefully lift the anemone from the old home and place it on the new one, "giving it several little taps with its big claws to settle it." ”

“ Among the jointed animals a wealth of interesting material is found by the embryologist. All crabs seemed to be modified lobsterlike creatures; to confirm this interpretation, based solely upon details of adult structure, young crabs pass through a stage when to all intents and purposes they are counterparts of lobsters. Even the twisted hermit crab, which has a soft-skinned hinder part coiled to fit the curve of the snail shell used as a protection, is symmetrical and lobster-like when it is a larva. ”

“ Of Crustacea, the Prawns and the smaller kinds of Crabs may be admitted to the aquarium, though but sparingly. They are rude, noisy, quarrelsome, and somewhat destructive,—but, for the same reason, amusing tenants of the tank.
All are familiar with the mode in which the Soldier or Hermit Crab takes possession of and lives in the shells of Whelks and Snails. Poorly protected behind by Nature, the homeless crab wanders about seeking a lodging. ”

“ The soft-bodied hermit crab as soon as he hatches out from the egg looks for a shell to fit his body in, to protect it from danger, and does the fitting and measuring of the shell with as delicate a nicety and circumspection as his seemingly more experienced older relatives. ”

“ If you want to see a curious sight get a hermit crab some day and pick up half a dozen empty shells of the size to fit him. Lay the shells on the sand in a circle a few inches across, extract the crab without hurting him from his house, and set him down naked among the empty shells. To get him out, by the way, is not so easy as it sounds, but you can do it by taking hold of his claws and maintaining a steady, gentle pull; in time the muscles of his tail will tire and his grip relax. ”

“ The hermit-crab is in fact a sea-gentleman, who is so unfortunate as to be born naked, and quite unable to make his own clothes, and who goes nervously about the world, trying on other people's cast-off coats till he finds one to fit him. ”

“ Little imagination is required to fancy that so light and delicate a body must be tenanted by some wandering fairy spirit.
[6] The large claws or pincers of some of these crabs are most beautifully adapted, when drawn back, to form an operculum to the shell, nearly as perfect as the proper one originally belonging to the molluscous animal. I was assured, and as far as my observations went I found it so, that certain species of the hermit-crab always use certain species of shells. ”

“ When the hermit grows too large to live comfortably in its shell, a change of home becomes necessary, and it is interesting to observe that the anemone living on the outside of the shell transfers itself at the same time; and this is a matter of vital importance to the crab, since it usually changes its lodging at the moulting period, at which time its body is covered by a soft skin, and is then even more acceptable as prey to the fishes. ”

“ During the proper phases of the moon we lead a most irregular life, for the hours from 3 to 5 A.M. are often the ones most profitable to spend on the reef, and the evenings are occupied with a search for hermit crabs. You have probably made the acquaintance of the hermit crab, but in case you have been too busy to give him the notice he deserves, I'll venture to dwell for a bit on his eccentricities. ”