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No. VII

On the first arrival of the crabs, when they throng the shoals of the creeks in vast crowds, as heretofore mentioned, a very summary way of taking them is resorted to by the country people, and for a purpose that few would suspect, without having witnessed it. They use a three-pronged fork or gig, made for this sport, attached to a long handle; the crabber, standing up in the skiff, pushes it along until he is over a large collection of crabs, and then strikes his spear among them. By this several are transfixed at once, and lifted into the boat, and the operation is repeated until enough have been taken. The purpose to which they are to be applied is to feed the hogs, which very soon learn to collect in waiting upon the beach, when the crab spearing is going on. Although these bristly gentry appear to devour almost all sorts of food with great relish, it seemed to me that they regarded the crabs as a most luxurious banquet; and it was truly amusing to see the grunters, when the crabs were thrown on shore for them, and were scampering off in various directions, seizing them in spite of their threatening claws, holding them down with one foot, and speedily reducing them to a state of helplessness by breaking off their forceps. Such a crunching and cracking of the unfortunate crabs I never have witnessed since; and I might have commiserated them more, had not I known that death in some form or other was continually awaiting them, and that their devourers were all destined to meet their fate in a few months in the stye, and thence through the smoke-house to be placed upon our table. On the shores of the Chesapeake I have caught crabs in a way commonly employed by all those who are unprovided with boats and nets. This is to have a forked stick and a baited line, with which the crabber wades out as far as he thinks fit, and then throws out his line. As soon as he finds he has a bite, he draws the line in, cautiously lifting but a very little from the bottom. As soon as it is near enough to be fairly in reach, he quickly, yet with as little movement as possible, secures the crab by placing the forked stick across his body, and pressing him against the sand. He must then stoop down and take hold of the crab by the two posterior swimming legs, so as to avoid being seized by the claws. Should he not wish to carry each crab ashore as he catches it, he pinions or spansels (as the fishermen call it) them. This is a very effectual mode of disabling them from using their biting claws, yet it is certainly not the most humane operation: it is done by taking the first of the sharp-pointed feet of each side, and forcing it in for the length of the joint behind the moveable joint or thumb of the opposite biting claw. The crabs are then strung upon a string or wythe, and allowed to hang in the water until the crabber desists from his occupations. In the previous article, crabs were spoken of as curious and interesting, and the reader may not consider the particulars thus far given as being particularly so. Perhaps, when he takes them altogether, he will agree that they have as much that is curious about their construction as almost any animal we have mentioned, and in the interesting details we have as yet made but a single step.

The circumstance of the external skeleton has been mentioned; but who would expect an animal as low in the scale as a crab, to be furnished with ten or twelve pair of jaws to its mouth? Yet such is the fact; and all these variously-constructed pieces are provided with appropriate muscles, and move in a manner which can scarcely be explained, though it may be very readily comprehended when once observed in living nature. But, after all the complexity of the jaws, where would an inexperienced person look for their teeth? – surely not in the stomach? – nevertheless, such is their situation; and these are not mere appendages, that are called teeth by courtesy, but stout, regular grinding teeth, with a light brown surface. They are not only within the stomach, but fixed to a cartilage nearest to its lower extremity, so that the food, unlike that of other creatures, is submitted to the action of the teeth as it is passing from the stomach, instead of being chewed before it is swallowed. In some species the teeth are five in number; but throughout this class of animals the same general principle of construction may be observed. Crabs and their kindred have no brain, because they are not required to reason upon what they observe: they have a nervous system excellently suited to their mode of life, and its knots or ganglia send out nerves to the organs of sense, digestion, motion, etc. The senses of these beings are very acute, especially their sight, hearing, and smell. Most of my readers have heard of crabs' eyes, or have seen these organs in the animal on the end of two little projecting knobs, above and on each side of the mouth: few of them, however, have seen the crab's ear; yet it is very easily found, and is a little triangular bump placed near the base of the feelers. This bump has a membrane stretched over it, and communicates with a small cavity, which is the internal ear. The organ of smell is not so easily demonstrated as that of hearing, though the evidence of their possessing the sense to an acute degree is readily attainable. A German naturalist inferred, from the fact of the nerve corresponding to the olfactory nerve in man being distributed to the antennæ, in insects, that the antennæ were the organs of smell in them. Cuvier and others suggest that a similar arrangement may exist in the crustacea. To satisfy myself whether it was so or not, I lately dissected a small lobster, and was delighted to find that the first pair of nerves actually went to the antennæ, and gave positive support to the opinion mentioned. I state this, not to claim credit for ascertaining the truth or inaccuracies of a suggestion, but with a view of inviting the reader to do the same in all cases of doubt. Where it is possible to refer to nature for the actual condition of facts, learned authorities give me no uneasiness. If I find that the structure bears out their opinions, it is more satisfactory; when it convicts them of absurdity, it saves much fruitless reading, as well as the trouble of shaking off prejudices.

The first time my attention was called to the extreme acuteness of sight possessed by these animals, was during a walk along the flats of Long Island, reaching towards Governor's Island, in New York, A vast number of the small land-crabs, called fiddlers by the boys (gecarcinus), occupy burrows or caves dug in the marshy soil, whence they come out and go for some distance, either in search of food or to sun themselves. Long before I approached close enough to see their forms with distinctness, they were scampering towards their holes, into which they plunged with a tolerable certainty of escape – these retreats being of considerable depth, and often communicating with each other, as well as nearly filled with water. On endeavouring cautiously to approach some others, it was quite amusing to observe their vigilance – to see them slowly change position, and, from lying extended in the sun, beginning to gather themselves up for a start, should it prove necessary: at length standing up, as it were, on tiptoe, and raising their pedunculated eyes as high as possible. One quick step on the part of the individual approaching was enough – away they would go, with a celerity which must appear surprising to any one who had not previously witnessed it. What is more remarkable, they possess the power of moving equally well with any part of the body foremost; so that, when endeavouring to escape, they will suddenly dart off to one side or the other, without turning round, and thus elude pursuit. My observations upon the crustaceous animals have extended through many years, and in very various situations; and for the sake of making the general view of their qualities more satisfactory, I will go on to state what I remarked of some of the genera and species in the West Indies, where they are exceedingly numerous and various. The greater proportion of the genera feed on animal matter, especially after decomposition has begun: a large number are exclusively confined to the deep waters, and approach the shoals and lands only during the spawning season. Many live in the sea, but daily pass many hours upon the rocky shores for the pleasure of basking in the sun; others live in marshy or moist ground, at a considerable distance from the water, and feed principally on vegetable food, especially the sugar-cane, of which they are extremely destructive. Others, again, reside habitually on the hills or mountains, and visit the sea only once a year, for the purpose of depositing their eggs in the sand. All those which reside in burrows made in moist ground, and those coming daily on the rocks to bask in the sun, participate in about an equal degree in the qualities of vigilance and swiftness. Many a breathless race have I run in vain, attempting to intercept them, and prevent their escaping into the sea. Many an hour of cautious and solicitous endeavour to steal upon them unobserved, has been frustrated by their long-sighted watchfulness; and several times, when, by extreme care and cunning approaches, I have actually succeeded in getting between a fine specimen and the sea, and had full hope of driving him farther inland, have all my anticipations been ruined by the wonderful swiftness of their flight, or the surprising facility with which they would dart off in the very opposite direction, at the very moment I felt almost sure of my prize. One day, in particular, I saw on a flat rock, which afforded a fine sunning place, the most beautiful crab I had ever beheld. It was of the largest size, and would have covered a large dinner-plate, most beautifully coloured with bright crimson below, and a variety of tints of blue, purple, and green above: it was just such a specimen as could not fail to excite all the solicitude of a collector to obtain. But it was not in the least deficient in the art of self-preservation: my most careful manœuvres proved ineffectual, and all my efforts only enabled me to see enough of it to augment my regrets to a high degree. Subsequently, I saw a similar individual in the collection of a resident: this had been killed against the rocks during a violent hurricane, with very slight injury to its shell. I offered high rewards to the black people if they would bring me such a one, but the most expert among them seemed to think it an unpromising search, as they knew of no way of capturing them. If I had been supplied with some powder of nux vomica, with which to poison some meat, I might have succeeded.

John.

No. VIII

The fleet running crab (cypoda pugilator), mentioned as living in burrows dug in a moist soil, and preying chiefly on the sugar-cane, is justly regarded as one of the most noxious pests that can infest a plantation. Their burrows extend to a great depth, and run in various directions; they are also, like those of our fiddlers, nearly full of muddy water, so that, when these marauders once plump into their dens, they may be considered as entirely beyond pursuit. Their numbers are so great, and they multiply in such numbers, as in some seasons to destroy a large proportion of a sugar crop; and sometimes their ravages, combined with those of the rats and other plunderers, are absolutely ruinous to the sea-side planters. I was shown, by the superintendant of a place thus infested, a great quantity of cane utterly killed by these creatures, which cut it off in a peculiar manner, in order to suck the juice; and he assured me that, during that season, the crop would be two-thirds less than its average, solely owing to the inroads of the crabs and rats, which, if possible, are still more numerous. It was to me an irresistible source of amusement to observe the air of spite and vexation with which he spoke of the crabs: the rats he could shoot, poison, or drive off for a time with dogs. But the crabs would not eat his poison, while sugar-cane was growing; the dogs could only chase them into their holes; and if, in helpless irritation, he sometimes fired his gun at a cluster of them, the shot only rattled over their shells like hail against a window. It is truly desirable that some summary mode of lessening their number could be devised, and it is probable that this will be best effected by poison, as it may be possible to obtain a bait sufficiently attractive to ensnare them. Species of this genus are found in various parts of our country, more especially towards the south. About Cape May, our friends may have excellent opportunities of testing the truth of what is said of their swiftness and vigilance.

The land-crab, which is common to many of the West India Islands, is more generally known as the Jamaica crab, because it has been most frequently described from observation in that island. Wherever found, they have all the habit of living, during great part of the year, in the highlands, where they pass the day-time concealed in huts, cavities, and under stones, and come out at night for their food. They are remarkable for collecting in vast bodies, and marching annually to the sea-side, in order to deposit their eggs in the sand; and this accomplished, they return to their former abodes, if undisturbed. They commence their march in the night, and move in the most direct line towards the destined point. So obstinately do they pursue this route, that they will not turn out of it for any obstacle that can possibly be surmounted. During the day-time they skulk and lie hid as closely as possible, but thousands upon thousands of them are taken for the use of the table, by whites and blacks, as on their seaward march they are very fat, and of fine flavour. On the homeward journey, those that have escaped capture are weak, exhausted, and unfit for use. Before dismissing the crabs, I must mention one which was a source of much annoyance to me at first, and of considerable interest afterwards, from the observation of its habits. At that time I resided in a house delightfully situated about two hundred yards from the sea, fronting the setting sun, having in clear weather the lofty mountains of Porto Rico, distant about eighty miles, in view. Like most of the houses in the island, ours had seen better days, as was evident from various breaks in the floors, angles rotted off the doors, sunken sills, and other indications of decay. Our sleeping room, which was on the lower floor, was especially in this condition; but as the weather was delightfully warm, a few cracks and openings, though rather large, did not threaten much inconvenience. Our bed was provided with that indispensable accompaniment, a musquito bar or curtain, to which we were indebted for escape from various annoyances. Scarcely had we extinguished the light, and composed ourselves to rest, when we heard, in various parts of the room, the most startling noises. It appeared as if numerous hard and heavy bodies were trailed along the floor; then they sounded as if climbing up by the chairs and other furniture, and frequently something like a large stone would tumble down from such elevations, with a loud noise, followed by a peculiar chirping noise. What an effect this produced upon entirely inexperienced strangers, may well be imagined by those who have been suddenly waked up in the dark, by some unaccountable noise in the room. Finally, these invaders began to ascend the bed; but happily the musquito bar was securely tucked under the bed all around, and they were denied access, though their efforts and tumbles to the floor produced no very comfortable reflections. Towards day-light they began to retire, and in the morning no trace of any such visitants could be perceived. On mentioning our troubles, we were told that this nocturnal disturber was only Bernard the Hermit, called generally the soldier-crab, perhaps from the peculiar habit he has of protecting his body by thrusting it into any empty shell, which he afterwards carries about until he outgrows it, when it is relinquished for a larger. Not choosing to pass another night quite so noisily, due care was taken to exclude Monsieur Bernard, whose knockings were thenceforward confined to the outside of the house. I baited a large wire rat-trap with some corn-meal, and placed it outside of the back door, and in the morning found it literally half filled with these crabs, from the largest-sized shell that could enter the trap, down to such as were not larger than a hickory-nut. Here was a fine collection made at once, affording a very considerable variety in the size and age of the specimens, and the different shells into which they had introduced themselves.

The soldier or hermit-crab, when withdrawn from his adopted shell, presents, about the head and claws, a considerable family resemblance to the lobster. The claws, however, are very short and broad, and the body covered with hard shell only in that part which is liable to be exposed or protruded. The posterior or abdominal part of the body is covered only by a tough skin, and tapers towards a small extremity, furnished with a sort of hook-like apparatus, enabling it to hold on to its factitious dwelling. Along the surface of its abdomen, as well as on the back, there are small projections, apparently intended for the same purpose. When once fairly in possession of a shell, it would be quite a difficult matter to pull the crab out, though a very little heat applied to the shell will quickly induce him to leave it. The shells they select are taken solely with reference to their suitableness, and hence you may catch a considerable number of the same species, each of which is in a different species or genus of shell. The shells commonly used by them, when of larger size, are those of the whilk, which are much used as an article of food by the islanders, or the smaller conch [strombus] shells. The very young hermit-crabs are found in almost every variety of small shell found on the shores of the Antilles. I have frequently been amused by ladies eagerly engaged in making collections of these beautiful little shells, and not dreaming of their being tenanted by a living animal, suddenly startled, on displaying their acquisitions, by observing them to be actively endeavouring to escape; or, on introducing the hand into the reticule to produce a particularly fine specimen, to receive a smart pinch from the claws of the little hermit. The instant the shell is closely approached or touched, they withdraw as deeply into the shell as possible, and the small ones readily escape observation, but they soon become impatient of captivity, and try to make off. The species of this genus (pagurus) are very numerous, and during the first part of their lives are all aquatic; that is, they are hatched in the little pools about the margin of the sea, and remain there until those that are destined to live on land are stout enough to commence their travels. The hermit-crabs, which are altogether aquatic, are by no means so careful to choose the lightest and thinnest shells, as the land troops. The aquatic soldiers may be seen towing along shells of the most disproportionate size; but their relatives, who travel over the hills by moonlight, know that all unnecessary incumbrance of weight should be avoided. They are as pugnacious and spiteful as any of the crustaceous class; and when taken, or when they fall and jar themselves considerably, utter a chirping noise, which is evidently an angry expression. They are ever ready to bite with their claws, and the pinch of the larger individuals is quite painful. It is said that, when they are changing their shells, for the sake of obtaining more commodious coverings, they frequently fight for possession, which may be true where two that have forsaken their old shells meet, or happen to make choice of the same vacant one. It is also said, that one crab is sometimes forced to give up the shell he is in, should a stronger chance to desire it. This, as I never saw it, I must continue to doubt; for I cannot imagine how the stronger could possibly accomplish his purpose, seeing that the occupant has nothing to do but keep close quarters. The invader would have no chance of seizing him to pull him out, nor could he do him any injury by biting upon the surface of his hard claws, the only part that would be exposed. If it be true that one can dispossess the other, it must be by some contrivance of which we are still ignorant. These soldier-crabs feed on a great variety of substances, scarcely refusing anything that is edible: like the family they belong to, they have a decided partiality for putrid meats, and the planters accuse them also of too great a fondness for the sugar-cane. Their excursions are altogether nocturnal: in the day-time they lie concealed very effectually in small holes, among stones, or any kind of rubbish, and are rarely taken notice of, even where hundreds are within a short distance of each other. The larger soldier-crabs are sometimes eaten by the blacks, but they are not much sought after even by them, as they are generally regarded with aversion and prejudice. There is no reason, that we are aware of, why they should not be as good as many other crabs, but they certainly are not equally esteemed.

John.