« ElőzőTovább »
Lobster is admirably formed for either running or swimming, and can bound with such a spring to her hole in the rock when frightened, that she enters it with velocity through an opening barely sufficient, to appearance, for her body to pass ; And the Pholas, though not furnished with an instrument apparently calculated for boring and scooping out stones, is endowed with such a fund of patient perseverance, that it is enabled to penetrate into these callous substances by the application of a fleshy member, resembling a tongue*.
THE INSTINCTIVE SAGACITY of the crustaceous tribe, also claims our attention. We have already remarked, that the little Nautilus is furnished with an apparatus for either diving or swimming. But who taught the Nautilus to sail ? - and yet, without the instinctive knowledge how to make use of them, of what use would be either her sails or oars; these, however, are not given her in vain, for she evinces a knowledge in the art of navigation, which is supposed to bave been copied by some of the early mariners, and the example she affords has been held out by the poet as still deserving imitation :
“ Learn of the little Nautilus to sail,
Sea of a small leg be' bruised, and the creature be laid on its back, it shews uneasiness at first, by moving it about, afterwards it holds it quite still, in a direct and natural position, without touching any part of the body, or of the other legs with it. Then, on a sudden, with a gentle crack, the wounded part of the leg drops off: the effect will be the same with the great leg, only it is thrown off with greater violence. Having got clear of the injured part, a mucus now overspreads the wound, which presently stops the bleeding; and a smali leg is by degrees produced, which gradually attains the size of the former.
Lobsters have also the power of reproducing an injured leg; and ihis accounts for them being so often found with limbs of unequal size:--the small leg must be a new one, which has not attained its full growth.
* With this soft and yielding instrument, the indefatigable and persevering Pholas, perforates marble and the hardest stones ; and when small and naked, it has effected an entrance; it then enjoys a life of security and ease, existing upon sea water that enters at the aperture, and increasing its habitation as it increases in size.
+ The natural sagacity of the Nautilus, in the use of his instruments of motion, is this beautifully delineated by the descriptive pen of
Sea Tortoises, without any teacher but nature, are instinctively taught to lay their eggs on the sea shore, and cover them with sand; and no sooner are the young hatched and fitted for their journey, than they leave the place of their nativity and run towards that element which provi. dence has destined for their abode ; so that the poet raay
“Reason progressive, Instinct is complete :
“Could know, or do, or covet, or enjoy. When the young Lobsters leave the parent, they betake themselves to hiding places in the smallest clifts of the rocks; but no sooner do they find themselves incrusted with a firm shell, than they sally out in quest of plunder. When the time of moulting, or changing the shell draws on, this animal again betakes itself to a retired situation, where it remains in security during its defenceless state*;
HERVEY: " The dexterous inhabitant, (whose shell forms a natural boat,) unfurls a membrane to the wind, which serves him instead of a sail. He extends also a couple of arms, with which, as with two stender oars, he rows himself along. When he is disposed to dive, be strikes sail; and, without any apprehension of being drowned, sinks to the bottom. When the weather is calm, and he has an inclina. tion to see the world, to take his pleasure, he mounts to the surface; and self-taught in the art of navigation, performs his voyage without either chart or compass; in himself the vessel, the rigging, and the pilot."
When the sea is calm, numbers of these animals are said to be seen sailing on its surface ; but at the approach of a storm, they fold in their legs, and swallowing as much water as will enable them to sink, they plunge to the bottom, where they no doubt remain in a place of security during the raging of the tempest, and when they wish to rise they void this abundant water, and so decreasing theis specific gravity, quickly ascend to the top, where, by means of their tails answering the purpose of helras, they can steer theinselves about in any direction.
* After losing the shell, (which both crabs and lobsters do annual. ly,) and before a new one is formed, the animal is in a very naked and defenceless state, exposed to the dog-fish, and a multitude of other depredators. In this situation they do not, however, long con tinue ; for the new covering is formed, and completely hardened, in little more than 48 hours.
no sooner bowever does it find itself covered with its new suit of armour, than it appears again on the stage, lively and active as before. The common Crabs herd together in distinct tribes, and keep their separate haunts*. The Soldier Crab is not provided by nature with a shell attached to his body, but she has inspired him with instinctive sagacity to take up his abode in the first empty one he can lay bold of, suitable to his purpose, and to change it for another when it grows incommodioust; and the Land Crabs of the West Indies (which also may be counted among the natives of the deep) are represented as living in a kind of orderly society, and regularly once a year marching down from the mountains to the sea, in spite of every intervening obstacle, in order to deposit their spawn; and after the little creatures are hatched under the sand, they also are observed as regularly quitting the shore in crowds, and slowly travelling up towards the moun. tains.
This has been tried by marking a crab, carrying it two or threo miles, and leaving it among other crabs. The crab has afterwards found its way home, and been caught in its old abode.
+ When it has overgrown, or otherwise has occasion to change the shell, the little soldier is seen busily parading the shore, but still dragging its old habitation along, unwilling to part with one, until it has found another shell niore convenient for its purpose. It is seen stopping at one shell, turning it, then going on to another, looking at it a while, then slipping its tail from the old habitation to try on the new. This is sometimes found to be more inconvenient, in which case, it quickly returns to its old shell, and goes in quest of another more roomy and commodious. But it is not till after many trials and frequent combats, that the soldier sometimes finds himself completely equipped ; for there are frequent contests betwixt two of this species, for some well-looking and commodious shell; and it is from this circum:tance, perhaps, the soldier-crab derives its name. When two of them meet with the same ohject, each strives to take possession; they strike with their claws; they bite each other till the weakest is obliged to yield. It is then the victor takes possession, and parades in his new conquest, backwards and forwards upon the strand before his envious antagonist.
1 These creatures commence their expedition in the months of April and May.-At that time the whole ground is covered with this numerous band of adventurers. The sea is the place of their destination, and to that they direct their march. No geometrician could send them by a shorter course. They never turn aside to the right or to the left, if they can possibly avoid it, whatever obstacles inter
When the Tellina bas occasion to move, she puts herself into a certain position, which occasions her to spring out with considerable force to a distance. When the Scallop finds herself deserted by the tide, it jerks itself forward by opening and shutting its shell in a singular manner! When the Razor Shell-fish, finds itself deceived by the fisherman, when he decoys it from its subterraneous habitation by a sprinkling of salt, and has time to retreat, no such attempt will succeed a second time !-When part of the legs of the Sea Hedge-hog are at work carrying him forward, the horns that are nearest in that direction are busily employed in making soundings or feeling the way.-The Muscle, when she has commenced spinning her cable, will make trial of a thread by drawing it out strongly tos
vene. If they meet with a house, they will attempt to scale the walls, in order to keep their ranks, and if the country be intersected by rivers, they wind along the course of the stream. They are com. monly divided into three battalions, of which the first consists of the strongest and boldest males, that, like pioneers, march forward to clear the rout, and face the greatest dangers. They are often obliga ed to balt for want of rain. The main body is composed of females, which never leave the mountains till the rain is set in, and then de scend in regular order, in columns of fifty paces broad, and three miles deep, and so close, that they almost cover the ground. Three or four days after this, the rear guard follows, a straggling and undisciplined tribe, consisting of males and females ; but neither so robust, nor so numerous as the former. The night is thuir chief time of proceeding, but if it rains by day, they do not fail to profit by the occasion. When they are terrified, they march back in a disorderly manner, bolding up their nippers, with which they sometimes tear off a piece of the flesh of an assailant, and leave the weapon where they inflicted the wound. They even try to intimidate their enemies, by clattering their nippers together, which, considering their number, must have a powerful effect. When they have arrived at the shore, which sometimes takes them three months, they prepare to cast their spawn, by eagerly gcing to the edge of the water, and letting it wash several times over their bodies. At the expiration of some days, spent on the land, after this washing, they again seek the shore, and shaking off the spawn into the water, leave it there. The sea, to : great distance is black with the eggs, and shoals of hungry fish atteod, and devour a cor:siderable quantity of them; those that escape are hatched under the sand; and soon after, millions at a time of these little crabs, are seen quiting the shore, and making their way slowly to the mountains.
The Bahama, and other American islanils, produce land crabs in great abundance, where they burrow in pairs in the earth.
wards her, before she proceeds to stretch out a second *!The Limpet when she has occasion to unmoor, finds means to disengage herself without any great effort, and to move from her place by the same muscle by which she adhered so firmly to her anchoraget. Eren. Oysters are said not to be destitute of the power and the instinctive sagacity to turn themselves round when thrown irregularly into a ves. sel of water, so that the concave shells may remain dowomost, in order to retain their favourite liquor.
USES OF SHELL-FISH. From the number of animals which
prey upon it was inferred, that the principal object the Creator had in view in the formation of these, was the subsistence of many of the larger orders of creatures ; so, from the namerous herds of shell fish, which in a great degree re
* These cords, which the Sea-muscle spins with so much art, are, in reality, as serviceable to them as cables are to a ship. There are frequently a hundred and fifty of these little cabies employed in mcoring a muscle ; each cable is scarcely too inches long, but they are all spun hy herself, and the tongue is the instrument which not only produces these numerous threads, but serves also instead of arms and legs on other occasions,
+ The Limpet has not been condemned to remain its whole life affixed to the same place ; it is necessary for it to go in search of food, and, notwithstanding its firm adhesion, when you attempt to raise it from the rock, it also possesses the power of motion, and it knows how to make use of it, and it is amazing what a simple, but powerful apparatus, it is provided with for the purpose. The principal cause of adhesion seems to be a viscous juice. or kind of glue, thrown out by the muscle which forms its lower surface ; this will be perceived by the strong hold it takes of the finger, when applied to the place from whence a limpet has been forcibly removed ; to dissolve this glue, therefore, is all that is necessary, but as the external water is kept at a distance by the close adhesion of the outer rim of the great circular muscle, the limpet must possess some other means of at least raising part of its surface ;--this it is enabled to do by the discharge of a small quantity of the water with which some of those tubercles
which cover the under part of its borly is found to abound, when the cement dissolves immediately, and it is set at liberty. Others of these cubercles are supposed to contain the viscous, or glue y matter, so that when it bas occasion to move, it has only to squeeze one set, and when it would affix itself, ibe other. Thus, as has been reinarked, the care of the Creator is obserable even in so incunsidérable a creature as a limpet: