spiracle, with six small cutaneous rays on their inner circumference; the mouth was small, the teeth minute and spicular; the colour of the animal was cinerous brown above and white beneath. The torpedo is an inhabitant of most seas, but seems to arrive at a larger size in the Mediterranean than elsewhere. It is generally taken with the trawl, but has been sometimes known to take a bait, thus justifying the description of Oppian. It commonly lies in water of about forty fathoms depth, in company with others of this genus.

It preys on smaller fish, and, according to Mr. Pennant, a surmullet and a place have been found in the stomach of two of them: the surmullet, as Mr. Pennant well observes, is a fish of that swiftness, that it would be impossible for the torpedo to take it by pursuit: we may therefore suppose that it stupi fies its prey, by exerting its electric faculty. The torpedo often inhabits sandy places, burying itself superficially, by flinging the sand over it, by a quick flapping of all the extremities. It is in this situation that it gives its most forcible shock, which is said to throw down the astonished passenger that inadvertently treads on the animal.

The torpedo, with respect to its general anatomy, does not materially differ from the rest of the ray tribe, except in its electric or Galvanic organs, which are thus accurately described by Mr. Hunter.

"These organs are placed on each side of the cranium and gills, reaching from thence to the semicircular cartilages of each great fin, and extending longitudinally from the anterior extremity of the animal to the transverse cartilage

abdomen; and within these limits they occupy the whole space between the skin of the upper and of the under surface: they are thickest at the edges near the centre of the fish, and become gradually thinner towards the extremities. Each electric organ, at its inner longitudinal edge, is a convex elliptic curve. The anterior extremity of each organ makes the section of a small circle; and the posterior extremity makes nearly a right angle with the inner edge. Each organ is attached to the surrounding parts by a close cellular membrane, and also by short and strong tendinous fibres, which pass directly across its outer edge to the semicircular cartilages. They are covered above and below by the common skin of the animal, under which there is a thin fascia, spread over the whole organ. This is composed of fibres, which run longitudinally, or in the direction of the body of the animal: these fibres appear to be perforated in innumerable places, which gives the fascia the appearance of being fasciculated: its edges, all round, are closely connected to the skin, and at last appear to be lost, or to degenerate into the common cellular membrane of the skin: immediately under this is another membrane, exactly of the same kind, the fibres of which, in some measure, decupate those of the former, passing from the middle line of the body outwards and backwards; the inner edge of this is lost with the first described; the anterior, outer, and posterior edges are partly attached to the semicircular cartilages, and partly lost in the common cellular membrane. This inner fascia appears to be continued into the electric organ by so many processes, and thereby make the

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membranous sides or sheaths of the columns, which are presently to be described; and between these processes the fascia covers the end of each column, making the outermost or first partition. Each organ is about five inches in length, and, at the anterior end, three in breadth, though it is little more than half as broad at the posterior extremity: each consists wholly of perpendicu ler columns, reaching from the upper to the under surface of the body, and varying in their lengths accord ing to the thickness of the parts of the body where they are placed, the longest column being about an inch and a half, and the shortest about one fourth of an inch in length, and their diameters about two tenths of an inch. The figures of these columns are very irregular, varying according to situation and other circumstances. The greatest number are either irregular hexagons, or irregular pentagons; but from the irregularity of some of them, it happens that a pretty regular quadrangular column is sometimes formed. Those of the exterior row are either quadrangular or hexagonal, having one side external, two lateral, and either one or two internal. In the second row they are mostly pentagons; their coats are very thin, and seem transparent, closely connected with each other, having a kind of loose net-work, of tendinous fibres, passing transversely and obliquely between the columns, and uniting them more firmly together. These are mostly observable where the large trunks of the nerves pass; the columns are also attached by strong inclastic fibres passing directly from the one to the other. The number of columns in different torpedos, of rather small size, appears to be about 470 in each organ, but the

number varies according to the size of the fish; and in a very large torpedo, the number of columns in one electric organ was 1182: they must, therefore, increase, not only in size, but in number, during the growth of the animal; new ones forming, perhaps, every year on the exterior edges, as they are much the smallest. This process may be similar to the formation of new teeth in the human jaw, as it increases. Each column is divided by horizontal partitions, placed over each other at very small distances, and forming numerous interstices, which appear to contain a fluid. These partitions consist of a very thin membrane, considerably transparent; their edges seem to be attached to each other, and the whole is attached by a fine cellular membrane to the inside of the columns. They are not totally detached from each other, and I have found them at different places adhering to each other by blood-vessels passing from one to another. The number of partitions contained in a column of one inch in length, of a torpedo which had been preserved in proof spirit, appeared, upon a careful examination, to be 150; and this number, in a given length of column, appears to be common to all sizes, in the same state of humidity; for by drying they may be greatly altered: whence it appears probable, that the increase in the length of a column, during the growth of the animal, does not enlarge the distance between each partition in propor tion to the growth, but that new partitions are formed, and added to the extremity of the column, from the fascia. The partitions are very vascular; the arteries are branches from the veins of the gills, which convey the blood that has received the influence of respiration. They

pass along with the nerves to the electric organ, and enter with them; then ramify, in every direction, into innumerable small branches upon the sides of the columns, sending in from 'the circumference all around, upon each partition, small arteries, which ramify and anastomose upon it; and, passing also from one partition to another, anastomose with the vessels of the adjacent partitions. The veins of the electric organ pass out close to the nerves, and run between the gills to the auricle of the heart, The nerves inserted into each electric organ, arise by three very large trunks from the lateral and posterior part of the brain. The first of these, in its passage outwards, turns round a cartilage of the cranium, and sends a few branches to the first gill, and to the anterior part of the head, and then passes into the organ near its anterior extremity. The second trunk enters the gills between the first and second openings, and, after furnishing it with small branches, passes into the organ near its middle. The third trunk, after leaving the skull, divides itself into two branches, which pass to the electric organ through the gills; one between the second and third openings, the other between the third and fourth, giving small branches to the gill itself.These nerves, having entered the organs, ramify in every direction between the columns, and send in small branches upon each partition, where they are lost. The magnitude and number of the nerves bestowed on these organs, in proportion to their size, must, on reflection, appear as extraordinary as the phænomena they afford. Nerves are given to parts either for sensation or action. If we except the more importaat senses of hearing, seeing, tast

ing, and smelling, which do not be long to electric organs, there is no part, even of the most perfect ani. mals, which, in proportion to its size, is so liberally supplied with nerves; nor do the nerves seem ne cessary for any sensation which can be supposed to belong to the electric organs; and, with respect to action, there is no part of any animal with which I am acquainted, however strong and constant its natural actions may be, which has so great a proportion of nerves. If it be then probable that those nerves are not necessary for the purposes of sensa tion or action, may we not conclude that they are subservient to the for mation, collection, or management of the electric fluid? especially as it seems evident, from Mr. Walsh's experiments, that the will of the ani mal does absolutely control the elec tric powers of its body, which must depend on the energy of the nerves."

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From the above description, it appears that the electric organs the torpedo constitute a pair of Galvanic batteries, disposed in the form of perpendicular hexagonal columns. In the Gymnotus electri cus, on the contrary, the Galvanic battery is disposed lengthways on the lower part of the animal.

We are informed by the ingenious Dr. Ingenhouz, that, on taking up some torpedos, about twenty miles from Leghorn, and on pressing gently with the thumbs on the upper side of the two soft bodies on each side of the head, (the electric or gans) in about the space of a minute or two, he felt a sudden trembling in the thumbs, which extended no farther than the hands, and lasted about two seconds, perfectly resem bling the sensation produced by a great number of very small electrical

bottles,

bottles, discharged in quick succession through the hands. After some seconds the sensation returned, and again at more distant intervals: sometimes it was so strong as almost to oblige the hand to let go the fish, and at other times was but weak; and, after the fish had given one strong shock, it did not seem soon to lose the power of communicating one of similar strength; and it was sometimes found, that when the shocks followed one another in quick succession, the last were stronger than the first.

The celebrated Spallanzani informs us, that some few minutes before the torpedo expires, the shocks which it communicates, instead of being given at distant intervals, take place in quick succession, like the pulsations of the heart; they are weak, indeed, but perfectly perceptible to the hand, when laid on the fish at this juncture, and resemble very small electric shocks: in the space of seven minutes, no less than three hundred and sixty of these small shocks were perceived. Spallanzani also assures us of another highly curious fact, which he had occasion to verify from his own experience, viz. that the young torpedo can not only exercise its electric faculty as soon as born, but even while it is yet a foetus in the body of the parent animal. This fact was ascertained by Spallanzani, on dissecting a torpedo in a pregnant state, and which contained in its ovarium several roundish eggs of different sizes, and also two perfectly formed fœtuses, which, when tried in the usual manner, communicated a very sensible electric shock, and which was still more perceptible when the little animals were insulated by being placed on a plate of glass.

The electricity of the torpedo is altogether voluntary, and sometimes, if the animal be not irritated, it may be touched, or even handled, without being provoked to exert its electric influence.

Natural History of the Land Salamander. By the Count de la Cepede.

It would appear that the more remote the objects of human curiosity are, the more man delights in attributing to them wonderful qualities, or at least in exaggerating those which being seldom thoroughly known, in reality possess the imagination, which, as one may say, from time to time, requires to be stimu lated with wonder; man wishes to give full scope to his belief, and he thinks he does not enjoy it with sufficient freedom when he subjects it to the laws of reason; he imagines that to use it he must carry it to the greatest excess, and does not consider himself as really master of it, unless when he capriciously refuses it to truth, or grants it to accounts of the most chimerical be ings. Man cannot exercise this em pire of fantasy but when the light of ruth shines from a distance upon the objects of this arbitary belief; but when the space, time, or their nature separate them from us; and for this reason among all classes of animals, there is perhaps none which has given rise to more fables than that of lizards. We have seen properties, as absurd as imaginary, ascribed to several species of ovi parous quadrupeds; but human imagination seems to have surpassed itself in the salamander, which has been thought to be endowed with the most_marvellous qualities. Whilst 3 F3

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the hardesi bodies cannot resist the violence of fire, the world have endeavoured to make us believe that a small lizard can not only with stand the flames, but even extinguish them.

As agreeable fables readily gain belief, every one has been eager to adopt that of a small animal so highly privileged, so superior to the most powerful agent in nature, and which could furnish so many objects of comparison to poetry, so many pretty emblems to love, and so many brilliant devices to valour. The ancients believed this property of the salamander, wishing that its origin might be as surprising as its power; and being desirous of realizing the ingenious fictions of the poets, they have pretended that it owes its existence to the purest of elements, which cannot consume it, and they have called it the daughter of fire*, giving it however a body of ice. The moderns have followed the ridiculous tales of the ancients, and as it is difficult to stop when one has passed the bounds of probability, some have gone so far as to think that the most violent fire could be extinguished by the land salamander. Quacks sold this small lizard, affirming that when thrown into the greatest conflagration, it would check its progress. very necessary that philosophers and naturalists should take the trouble to prove, by facts, what reason alone might have demonstrated; and it was not till after the light of science was diffused abroad, that the world gave over believing in this wonderful property of the salamander.

It was

This lizard, which is found in so

many countries of the ancient world, and even in very high latitudes, has been, however, very little noticed, because it is seldom seen out of its hole, and because for a long time it has inspired much terror. Even Aristotle speaks of it as of an animal with which he was scarcely acquainted.

It is easy to distinguish this li. zard from all others, by the particular conformation of its fore feet, which have only four toes, while those behind have five. One of the largest of this species, preserved in the king's cabinet, is seven inches five lines in length, from the end of the muzzle to the root of the tail, which is three inches eight lines. The skin does not appear to be covered with scales, but it is furnished with a number of excrescences, like teats, containing a great many holes, several of which may be very plainly distinguished by the naked eye, and through which a kind of milk oozes that generally spreads itself in such a manner as to form a transparent coat of varnish above the skin of this oviparous quadruped, naturally dry.

The eyes of the salamander are placed in the upper part of the head, which is a little flatted; their orbit projects into the interior part of the palate, and is there almost surrounded by a row of very small teeth, like those in the jaw bones: these teeth establish a near relation between lizards and fishes; many species of which have also several teeth placed in the bottom of the mouth. The colour of this lizard is very dark; upon the belly it has a bluish cast, intermixed with pretty large irregular yellow spots, which