with a stomach of wonderful force and thickness, and far exceeding that of any other creature. Whatever their force of digestion is, it has no effect upon their young ones, which always retreat into their stomachs in time of danger. That digestion is not performed by heat in fish, is equally evident. The coolness of the stomach of these fishes is far greater than the temperature of the water out of which they are taken; or of any other part of the fish, or of any other substance of animated nature I ever felt. On wrapping one of them round my hand, immediately on being taken out of the fish, it caused so much aching and numbness that I could not endure it long. Of these voracious sea monsters, there are thirty three species."

THE TORPEDO.-The torpedo inhabits the Mediterranean and the North Seas, and grows to the weight of twenty pounds This fish possesses a strong electrical power, and is capable of giving a very considerable shock through a number of persons forming a communication with it. This power was known to the ancients, but exaggerated by them with all the fables natural to ignorance; and it is only recently that the power has been ascertained to be truly electric. It is conducted by the same substances as electricity, and intercepted by the same. In a minute and a half, no fewer than fifty shocks have been received from this animal, when insulated. The shocks delivered by it in air, are nearly four times as strong as those received from it in water. This power appears to be always voluntarily exercised by the torpedo, which oc casionally may be touched and handled without its causing the slightest agitation. When the fish is irritated, however this quality is exercised with proportional effect to the degree of irritation; and its exercise is stated, in every instance, to be accompanied by a depression of the eyes. When that animal exerts the benumbing power, from which it derives its name, and when it operates by separate and repeated efforts, this is always the case. Both in the continued, and in the instantaneous process, the eyes, which are at other times prominent, are withdrawn into their sockets; a circumstance very naturally attaching both to the condensation and discharge of the subtle fluid. Specimens have been known of this fish weigh ing fifty, and even eighty pounds. It commonly lies in forty fathoms of water, and is supposed to stupify its prey by this extraordinary faculty. It is sometimes nearly imbedded in the sands of shallows; and it is stated, in these cases, to give to any who happens to tread upon it, an astonishing and overwhelming shock. On dissection, it was found to exhibit no material difference from the general structure of the ray excepting with respect to the electric or galvanic organs,

which have been minutely examined and detailed by the cele brated anatomist, John Hunter: he states them "to be placed on each side of the cranium and gills, reaching thence to each great fin, and extending longitudinally from the anterior extremity of the animal, to the transverse cartilage which divides the thorax from the abdomen.”

From the whole description, it appears that these organs, as Mr. Shaw observes, constitute a pair of galvanic batteries, disposed in the form of perpendicular hexagonal columns; while, in the gymnotus electricus, the galvanic battery is disposed lengthwise on the lower part of the animal. It is stated, that the torpedo, in its dying state, communicates shocks in more than usually rapid succession, but in proportional weakness; and in seven minutes, in these circumstances, three hundred and sixty small shocks were distinctly felt. On the same authority (that of Spallanzani) it is reported, that the young torpedo can exercise this power at the moment after its birth, and even possesses it while a foetus, several of these having been taken from the parent fish, and being found to communicate perceivable shocks, which, however, were most distinctly felt when these animals were insulated on a plate of glass.

A very curious object is, THE AIR-BLADDER IN FISHES.There is no doubt that fishes extract air from water by means of their gills, since it is through them that they renew the air of their air-bladder. This bladder is an oblong bag, consisting of two or three membranes easily separated; sometimes it has only a single lobe or cavity, as in the case of pikes, whitings, trouts, &c.; at other times it has two lobes, as in the case of barbel and carp; three, as in that of the sea tench; or four, as in the Chinese gold fish. It is by expanding or compressing this bladder, that the fish occupies more or less space in the water, becomes more or less heavy, and ascends or descends as it chooses. The division of the bladder into different lobes has proceeded from a very sufficient reason. When the bladder has only one cavity, as in the case of fishes of prey, the motion of ascent or descent takes place slowly, and without a break; because, as they compress the whole bladder at once, the whole body is moved horizontally, upwards or downwards, as the case may be; a circumstance which has the effect of lessening, in consequence of the resistance of the water, the swiftness of those Lyrants of the deep. When the bladder has two lobes, as in the case of the carp, which lives on insects, that fish, by expanding the anterior and compressing the posterior lobe, rises rapidly with the head foremost to the surface of the water, or sinks to the bottom with equal expedition, by compressing its two lobes in different ways. The consequence is,

an increased promptitude of movement, and additional means of escaping from its enemies. When the bladder has four lobes, as in the case of the gold fish, that fish is thus enabled to vary greatly its contractions and expansions. It rises, sinks, bends, erects, or turns itself in a thousand ways, and plays in the water, like a bird in the air. It displays all the richness of the colours of gold, silver, or purple, with which Nature has adorned it. Its attitudes are so graceful, and its movements so varied, that the Chinese, from whom we originally received it, are said to pass whole days in looking at it, in the basins of the fountains in their gardens, or in crystal vessels. It is evidently indebted for the ease and grace of its motions, to the modulations consequent on the four divisions of its air-bladder.

Another subject of curiosity is, THE RESPIRATION IN FISHES.-Fish derive air from the water which they are inaccessantly swallowing through the mouth, and throwing out by the gills. The gills are formed with infinite skill, and may be called a delicate kind of sieve, adapted for separating air from water. Their operation proves the radical difference between these two elements, and leads to the conclusion, that . they are not joined even when mixed. The gills are placed in the back part of the sides of the head, and are contained in a cavity adapted for them. They are a kind of red and flexible leaflets, consisting of a row of thin plates, like the blade of a knife, pressed against each other, and forming a succession of barbs or fringed substances, similar to those on the side of a goose-quill. These gills are covered with a small lid, and with a membrane, supported by cartilaginous threads. Both are capable of being raised and lowered; and, by being thus opened, they afford a passage to the water swallowed by the animal. A prodigious number of muscles give motion to these minute particles. It may appear almost incredible, that the number of particles connected with the respiration of the carp is not fewer than 4386. Of these, sixty-nine are muscles; while the arteries of the gills, in addition to eight principal branches, throw forth 4320 smaller ramifications, while each of the latter gives birth to a number of cross arteries. Add to this, that the quantity of nerves is not smaller than that of the arteries; and that the veins are divided and subdivided, like the arteries, inasmuch as they do not give rise to any transverse capillary vessels. In this manner the blood flowing from the heart of the fish is spread over all the plates or blades of which the gills are composed; so that a very small quantity of blood is exposed to the action of the water, for the purpose, no doubt, that each part may be easily penetrated by the particles of air detached from the water.