the surface of the ocean fparkles, and fhines throughout its whole extent like a filver stuff electrified in the dark; there the waves roll out in immense sheets of fulphur and bitumen in flames; in other parts again the fea resembles a vast ocean of milk, the limits of which are loft in the horizon. Bernardin de St. Pierre has defcribed, with enthusiasm, the brilliant stars which by myriads fpring from the bottom of the fea, and of which he observes with truth, our fireworks are but a feeble imitation. Others speak of those maffes, in guife of fire, which roll over the waves like fo many red-hot balls, and of this defcription we ourselves faw one apparently not lefs than 20 feet in diameter. Many failors have noticed incandefcent parallelograms, cones of light revolving round their own axes, fplendid garlands, and ferpentining illuminations. In fome parts of the fea columns of fire, eliciting fparks, are thrown up from the bofom of the deep in others, clouds of light and phosphorus are seen traversing the waves in the midst of darkness. Occafionally the ocean appears decorated with an immenfe fcarf of moveable and wavy light, the ends of which exceed the limits of fight. All these phenomena, and many other which I abstain from indicating here, however marvellous they may appear, are not the lefs inconteftable; they have been defcribed by travellers of undifputed veracity, and I myself have obferved the major part of them in different quarters of the fea. How numerous the theories which fucceffively have been publifhed to explain these kinds of prodigies! Now the fpirit of falt, bitumen, petroleum, and animal oil, have been held forth as the elements of thefe varied phenomena; the spawn of fifh now, of mollufca and the remains of fea animals; and now again, the gelatinous mucus which tranfudes from fifh continually, from zoophytes, mollufcæ, &c.; fome naturalifts have afcribed it to a fpecies of movement of putrefaction in the fuperficial beds of the ocean; many have called light to their affiftance for expounding the mystery; and while fome imagine it acting in combination, others confider it as exclufively reflected. Electricity could but act a principal part in this quality of the fea with many, and numbers of celebrated characters have attributed the phofphorefcence to its agency. More recently ftill, phofphorus, and its divers combinations, have opened a new field for hypothefis; fome have fuppofed it in thefe phenomena to be in a pure state, and others combined with hydrogen.-In fhort, there are no kinds of explanation, likely, or abfurd, which have been omitted; and, nevertheless, the opinion of strict naturalists continues yet uncertain as to the real caufe of this grand phenomenon of nature. In the phyfical and meteorological part of my works, I fhall have occafion to examine more particularly thefe different theories, and fhall, I truft, be able to fhew how much, one of them excepted, they are inadequate to the folution of the different data of the problem; here I fhall merely publish fome of the refults of my experiments and long researches into the fubject. 1. Phofphorefcence effentially pertains to all feas; it is alike obfervable in the middle of the equatorial regions, in the feas of Norway, and Siberia, and in thofe of the antarctic pole. moft precife, and leaft fufceptible of enthufiafm or exaggeration. It will be fufficient I fhould fpecify the names of Cook, La Peroufe, Labillardiere, Vancouver, Banks, Sparmann, Solander, Lamanon, Daprès de la Mannevilette, Le Gentil, Adamfon, Fleuricu, Marchand, Stavorinus, Spallanzani, Bourzeis, Linnæus, Pifon, Hunter, Byron, Beal, Adler, Rathgcb, Martens, De Gennes, Hierne, Dagelet, Diequemarre, Bacon, Lefcarlot, Laflingius, Shaw, Sloane, Tachard, Dembey, Ozanam, Barter, Tarnftröm, Marfigli, Kalm, Naffau, Pontoppedan, Morogue, Phipps, Poutrincourt, Heittman, Kirchmayer, Anfon, Frezier, Le Maire, Vannei, Rhumpe, Rogers, Drake, &c. 2. Circum 2. Circumstances alike, phosphorescence is generally more powerfully exhibited and more conftant between the tropics, or near to them, than in latitudes more towards the poles. 3. The conftantly warmer temperature of the equinoxial feas appears to be the mediate cause of this difference. 4. Under fimilar circumftances, phofphorescence exifts on a grander scale and more constantly along coafts, in narrow feas and ftraits, than in wide extending feas and at distance from land. 5. Commonly this phenomenon is apparent in proportion to the roughness of the fea, and the darkness of the night. 6. It is however perceptible even in the calmeft weather, and the brightest moonlight. 7. All the phenomena of the phosphorefcence of fea water, however multiplied and fingular, are afcribable to one caufe, the luminoufnefs attached to fea animals, and most especially to mollufcæ, and other foft zoophytes. My numerous experiments, and the beautiful series of phosphorescent animals executed by M. Lefueur, will I trust empower me to remove all rational doubt of this important truth. 8. The active phofphorefcence inherent in animals, different in every respect from the weak light, which in certain inftances emanates from putrid decompofition, is fo completely dependent on the organization and life of thefe animals, that it increases with their growth, diminishes with their decay, becomes extinct with their life, and after death is incapable of reproduction. SECT. V.-Obfervations pertaining to Natural History. HOWEVER varied my obfervations on phyfics and meteorology, they did not abforb all my time; fo much may there be bestowed to study on board of fhip, where, far from the bufy hum of cities, man finds himself fo completely removed from all family duties, or the courtefies of friendship, from all relations in fhort of fociety. The study of mollufcæ, or pelagic zoophytes, in particular, employed all my leifure moments: it had been most especially recommended to me by M. Cuvier, who may, if the expreffion is allowed, be looked upon as the creator of this important clafs of the animal kingdom, and whofe counfels and inftructions ferved to regulate my enquiries. My colleague Maugè, my friend Lefueur, worked with me in concert, and we had the grateful fatisfaction to make, in this study, discoveries equally numerous and interesting; but the detail of these being incongruous to our narrative, it will fuffice I prefent, in a rapid sketch, a picture of fome of these animals, too long neglected by naturalifts, and which, by the fingularity of their form, their extraordinary organization, the beauty of their hues, and the variety of their habitudes, fo richly merit the attention of the enlightened part of the community. Åt the head of these animals presents itself the Phyfale, a species of zoophytes which, by means of a membranous bladder, much resembling that of certain fifh, always floats on the furface of the fea; a fort of mufcular and membranous ridge, which rifes longitudinally in folds from the upper part of the inflated veficle, furnishes the animal with a real fail, the dimenfions of which it can vary at pleasure, to fuit the force and direction of the wind; to this fingularity, no doubt, are attributable the names by which it is diftinguished, of frigate, gaelette, galley, &c. names given it by failors of all nations: a treacherous animal, it extends over the furface of the water numerous feelers, several feet in length, of an ultramarine blue colour extremely lively and bright. Woe to the hand hand that ventures to lay hold on them; the fenfation of a burn is not more fudden than that of the hidden poison of these inftruments of prey. An infupportable pain in the part touched by them, and a complete numbnefs in the correfponding limb, are the almost instantaneous effects of the flightest contact. Sometimes little white blifters are raised on the skin, fimilar to thofe occafioned by ftinging nettles, caufing a very poignant smart, which generally lafts from twenty-four to fix-and-thirty hours. What is the nature of this fubtle poifon? No pofitive experiment has hitherto been made of it; all that I can fay myself from trial is, that on immerging this animal in water strongly impregnated with any acid whatever, and especially fulphuric or muriatic acid, the beautiful blue colour of its feelers immediately became red, as if the element of their colour was of a vegetable nature. I must add, this fifh feems to poffefs a specially stupifying power over the animals on which it feeds; for, otherwife, it would be impoffible to conceive how an animal fo weak as the phyfale can retain in its nets, and in a manner devour alive, fishes four or five inches in length, as we had frequent opportunities of observing. For this laft purpose, the galley employs a prodigious number of fuckers, which depend from the lower part of the airy veficle, and which are furrounded by the poisonous feelers I have described. Next to the phyfales in interest are the Phyffophores; foft, gelatinous animals of the moft beautiful colours; their bodies are fupported on the waves by means of a veficle, of the shape of a very fmall olive, and with a very thick coat, the interior of which is filled with air. Is the animal folicitous of plunging into the deep, a valve falls, the air by which the bladder is inflated escapes, the specific gravity of the animal increases, and it finks. Does it wish to re-afcend, a new bubble of air feems to be developed, or rather inftantaneously created, the little refervoir again extends its fides, the valve closes, and the phyffophore, now rendered buoyant, rifes to the furface of the fea. The Vetelles obtain the fame end from different means; on the back of the animal, which presents the figure of a small wherry with its bottom upwards, a fort of crest or ridge, extremely thin, light, tranfparent, and cartilaginous, rifes in an oblique manner; this is a large fail which ferves the vetelle to direct its movements, and to vary and increase their velocity: always keeping close to the wind, this elegant azure boat advances in order, tacks with rapidity, and changes its courfe according to its pleasure or need, and rarely fails of attaining the prey it purfues: this overtaken, it enfolds it within its numerous feelers, difpofed round the boat, and devours it by means of the multiplex fuckers which hang from its lower exterior. The elegance of the form of this animal, the tranfparency of its fail, the beautiful mantle of blue with which it is clad, all concur to render it one of the most pleafing fpecies of the family to which it belongs; indeed, nothing can afford a more charming picture than these animals, when, in calm weather, they manoeuvre by thousands on the furface of the fea, and refemble fo many gay flotillas, directed by the fame principles employed in naval tactics by man. In the Beroes nature feems to have exhausted herself to produce the utmost grace and brilliancy in the elegance of its figure, the richness of its hues, and the variety of its movements. The fubftance of them, fuperior in pellucidity to the cleareft cryftal, is generally of a beautiful rofe-colour, that of the opal, or azure; their form is more or lefs fpheroidic eight or ten longitudinal ribs are difpofed around it, each formed of a prodigious number of fmall tranfverfal leaves, extremely thin, and of aftonishing mobility: these constitute the essential organs of motion of the animal. By the help of thefe myriads of little paddles, worked at pleasure, this animal directs its courfe at will. towards its prey, to avoid an enemy, or in circular revolution about its own axis; by thefe, thefe, in fhort, it effects whatever manœuvre it needs. What is still more admirable in the beroes, light being decompofed by the effect of its movements, equally rapid as various, its longitudinal ribs become as many living prifms, and envelope the animal like eight or ten rainbows, fo animated, and fo undulating, that language or the pencil muft in vain attempt to defcribe their beauty. What fhall I fay now of that other fpecies of zoophytes, which, fimilar to a beautiful wreath of cryftal of an azure hue, fwims on the furface of the waves, and lifts above them in fucceffion its diaphanous leaflets, in figure resembling thofe of ivy! Its beautiful rofy feelers extend to a diftance in fearch of its prey; it touches it, and inftantly it is caught in the fatal net. The animal then contracts itself fo as to form a kind of circle round the food it has feized. Myriads of fuckers, comparable to long leaches, dart at the fame inftant from the leaflets I have noticed, and which, in a state of rest, serve to cover and protect them. Paffed but a few feconds, and the most bulky prey is no longer to be feen. Shall I dwell on the admirable phofphorefcent property common to the majority of animals of this class, but which in this manifests itself in a more than ufually lively and fplendid degree, and which in the midft of darkness gives it the fimilitude of a garland of fire and light? What fhall I fay alfo of thofe Tanthines, of a purple colour, which make their way over the furface of the waves fufpended by a white bunch of airy bladders? Of thofe numerous legions of Salpa, of a rofy, azure, or an opal colour, which form floats of thirty or forty leagues in extent, and fhine with fplendour in the dark? Of thofe Medufæ, equally phosphorefcent, which prefent fo many fingular forms in their organization, fo many delicate fhades of colour? Of those Pyrofomes fhaped like an enormous finger of a glove, which exhibit no apparent loco-motive organ, no organ of digeftion, or of reproduction even, but which cover the fea with their innumerable hofts. The fubftance of these animals is brilliant in fuch a degree, during the prevalence of darknefs, as to affimilate with molten iron! Shall I here defcribe thofe charming Glauci, of an ultramarine blue, with a filver band on the back, which resemble fo many pelagic lizards? Their gills (branchia) ramified like handfome fhrubs, ferve them at once to fwim with and for lungs. Shall I recall to mind those Pneumodermes which the celebrated M. Cuvier, to whom I fent feveral fpecimens, conceives fhould conftitute a new order* in the class to which they belong, and which have the organ of respiration on the pofterior part of the back? Shall I fpeak of those Hyales, whofe cantonments are the vicinage of the Cape of Good Hope, and which, protected only by a fhell, extremely thin, fragile, light, diaphanous, and horny, yet delight in the ftormy waves of the Southern Ocean? One is tempted to take these beautiful mollufcæ, on feeing them display their purple fins, for fo many turtles in miniature; and, in fact, it is by that name they are defignated by failors. Shall I dwell on the difcovery of the living Spirula, which at length refolves the great problem of the mode of formation of thofe fingular fhells with feveral cells, which, under the names of Nummulites, Belemnites, horns of Ammon, Hippurites, lenticular ftones, Turrilites, &c. are of fuch note in the history of the revolutions of our planet, of which so small a number of fpecies fhould feem to have escaped the great catastrophes of nature, and the living animals pertaining to which were hitherto unknown to naturalifts? Shall I defcribe those azure Porpites, in the membranous fhell of which the learned M. Cuvier fancies a recognition of the type of fome fpecies of nummulites with concen* Annales du Mufæum d'Hiftoire Naturelle, No. 21, p. 2 . |