ing of fishes. The celebrated naturalist Milne Edwards, a member of the French Institute, was appointed by the government to examine the proceedings of these persons, and after an elaborate investigation, he made a report fully verifying their success. The attention of M. Coste, Professor in the College of France, had been drawn to this subject, and investigating it with admirable sagacity, he published his views, thus spreading before the world all the facts necessary to the actual and practical culture of fishes. The question of priority of discovery between various parties has given rise to some controversy, the result of which seems to be that Messrs. Géhin and Remy are entitled to the credit of having commenced, as early as 1842, the artificial fecundating of the eggs, and breeding fishes from them, this being the true point of discovery. That this could be done was of course known to naturalists so accomplished as Milne Edwards and Professor Coste, and when they found it to be not only practicable, but practiced with positive success, they added the lights of science to the discovery, thus establishing and extending its utility. The experiments of Professor Coste, especially, were of the greatest practical importance, and the results of his investigations being published, speedily disseminated the knowledge which had been acquired, over the world. In France the government founded an establishment at Huningen, in the department of the Upper Rhine, which went into operation in 1852, and has been entirely successful in breeding fishes; being a government establishment, it supplies eggs of the best varieties to every department of France. The actual product of fishes by artificial breeding in France at the present time is great, and promises to be of the utmost national importance. In England, Mr. Boccius, a civil engineer, appears to have been employed in the artificial breeding of fishes as early as 1841, that is, a year prior to the first attempts of Géhin and Remy, and being successful, had as early as 1842 hatched in various streams as many as two millions of trout. In 1853 the breeding of salmon was commenced at Stormontfield, near Perth, in Scotland, and the results were truly marvelous. In May, 1854, about two hundred thousand smolts, which had been hatched in the ponds, were put into streams connected with the sea. At this time they were about seven inches long, and weighed half an ounce to two ounces. In August they returned, and having been marked, were easily recognized. It was found after an absence. of two months they had increased to three, five, seven, and even nine pounds in weight!

The fact that trout, salmon, pike, and other fishes may be thus artificially bred, and with enormous profit, is well established by these and many other experiments in different parts of Europe. Experiments have been made in this country, especially by Robert L. Pell, Esq., at Pelham, Ulster County, New York, and by Dr. T. Garlick and Prof. H. A. Ackley, of Cleveland, Ohio, and indeed by many others, verifying the general results which we have stated as having been ob

which Mr. Géhin could not precisely determine, the little fish appear about the size of pins, come out of their cells between the interstices of the gravel, and seek in the tranquil waters, near the shore, a place of safety.

Having thus discovered nature's secrets, it remained to discover a mode of rendering them practically useful, and not until after many failures did Géhin and Remy hit upon a sure process, incontestably superior even to that of nature herself. This may be deemed too bold an assertion, but a moment's reflection will prove its truth." * The discovery and practice of the artificial breeding of fishes date back as far as 1763, when the results of thirty years' research on the part of a German named Jacobi, were published in Hanover. In this memoir, it appears that the author proceeded upon an exact knowledge of the habits of trout, salmon, &c., and imitating them, he actually hatched and propagated fishes in nearly the same manner as was afterward done by Géhin and Remy, Professor Coste and others. The knowledge of these facts, certainly in the possession of scientific men, still appears to have lain practically dormant for nearly a century; but in 1837, Mr. Shaw, and soon after Mr. Boccius, commenced making experiments in England, probably instigated by the discoveries of Jacobi. They were entirely successful, and the result has been the actual breeding of fishes in Great Britain to a very large extent. The operations of Géhin and Remy began at a later date, that is, in 1842; but they proceeded without instruction from any extraneous source, and though not the first to discover and put in practice this new art, they were real inventors, and in consequence of the enlightened and energetic following up of their system by the French government, have been the means of a rapid dissemination of knowledge on the subject throughout the civilized world.

It appears by the late work on Pisciculture, by Eugène Noël, that in the Encyclopédie Nouvelle, published in Paris, in 1842, a note was added to the article Organogénie, by Dr. Serres, in which the following passage occurs: "The physiologist can put in a vase, eggs not fecundated, and in another zoosperms; in pouring the latter upon the former, he creates animals at will." Here seemed a general philosophic statement of the principle of the system of which we are treating.

It may be added that, according to the authority of M. Coste, it was by recourse to this method of multiplication that Messrs. Agassiz and Voght procured all the embryos necessary for their studies on the development of the Palée, a species of salmon in the Swiss lakes, the anatomical history of which these two naturalists published in 1842.

tained in Europe.* The stocking of barren or impoverished rivers, lakes, and ponds by fishes artificially hatched, may be considered as not only a possibility in this country, but as a means of easy and certain supply, demanding the attention of patriots and statesmen.

We cannot here enter into an account of the various methods adopted for the breeding of fishes, but must refer the reader to the work on this subject by W. H. Fry, Esq., published by Appleton & Co., 1854, and the still more recent publication by Dr. Garlick, of Cleveland, Ohio. We may state, however, that the new art of propagation has been successfully applied in Europe to the production of salmon, trout, shad, pike, carp, bream, barbel, tench, and perch, and in this country to several of these species. It is ascertained that all these fishes, filled with roc, and near their spawning-time, may be transported for hundreds of miles; the eggs of the female may be pressed out by the hand, and the milt, extracted in the same manner, strewn over them; thus prepared, they may be put in artificial or natural enclosures, with beds of gravel, and left to be hatched. The particular devices employed are various, but they are all simple. Some of the establishments in England and France are on a large scale, and the product is truly astonishing.†

* In the Transactions of the American Institute of the City of New York, for 1857, p. 439, will be found an interesting and instructive essay, by Mr. Pell, on American fishes and fish-breeding, by which it appears that he has met with the most entire success in the artificial breeding of various species. The experiments of Dr. Garlick and Professor Ackley have been chiefly made on the fishes of Lake Erie and the vicinity. Their method of proceeding appears to be alike practical and successful. They seem specially to note the following fishes as suitable for artificial propagation: the BLACK BASS, Grystes nigricans of Agassiz, or Centrarchus fasciatus of De Kay; the LARGE-MOUTHED Bass, G. megastoma; the WHITE BASS OR WHITE PERCII, Labrax multilineatus; the GRASS BASS, Centrarchus hexacanthus ; ROCK BASS, C. æneus; and the Common Pickerel, Yellow Perch, Sun-Fish, and Common Eel.

We find the following in the papers, April, 1859:

"A remarkable account has been lately given by Dr. Cloquet to the Paris Société d'Acclimation, of the results of an attempt to keep salmon in fresh-water ponds having no communication with the sea. The experiment was made near St. Cloud, where M. Coste has successfully carried on piscicultural operations on a very extensive scale. The pond chosen for the experiment in question is of small extent, and is supplied by a small stream of fresh water, sufficient to form a cascade. Three years ago the pond was entirely emptied and cleaned out. In April and May, 1855, several thousand salmon, only two months old, were placed in the pond with trout, and, notwithstanding the voracious nature of the latter fish, the salmon have prospered so well that a few weeks ago, in the presence of the emperor, who takes great interest in the artificial propagation of fish, no less than four hundred pounds' weight of salmon was caught by one haul of a net. This result is very surprising, but M. Coste states that he was far more astonished to find that the female salmon were full of eggs! He adds that he saw several eggs so highly developed that they were on the point of being emitted. These results, which bear the stamp of high authenticity, prove that salmon may be produced and reared in fresh-water ponds under similar circumstances to those by which trout are now so successfully multiplied in various waters around Paris."

We now take leave of the Vertebrate Division of the Animal Kingdom, and enter upon another, formed upon altogether a different type. We have just quitted the fishes, properly so called, but we have not yet done with the sea, their home. Notwithstanding the infinite number of swimming fishes, there is still abundant room in the ocean and its accessories—bays, sounds, gulfs, rivers, and lakes-for another race of beings, infinitely diversified in form, and countless as the leaves of the forest.

The Mollusca, our present theme, bear the general name of Shell-fish, though they do not embrace all that is included in that title. Lobsters, crabs, prawns, and many other creatures that live in the sea, belong to another division: we now treat of oysters, clams, cockles, snails, mussels, and a variety of others, which produce the beautiful and diversified shells which ornament the cabinet of the conchologist. Though the study of these might seem little likely to afford amusement, we may remark that it is precisely here in this almost hidden and lost division of the animal kingdom, that we shall meet with some of the most interesting and instructive surprises. Every living creature has a history of its own; each has characteristics by which it may be known from its relatives; each has its own territory, its appropriate food, and its duties to perform in

the economy of nature. An account of these is their natural history, and this is likely to prove interesting, somewhat in proportion to the peculiarities of the creatures themselves, and the novelty of the revelations which their powers, instincts, and habits unfold.

nerves.

Throughout all the classes of animals we have described, we have found an internal bony skeleton, forming the foundation for the whole structure of the body-limbs, flesh, muscles, and In the Mollusca the bodies are soft, and instead of having an internal bony support, they are mostly protected by a hard external shell. These soft bodies are enveloped in a muscular skin, which naturalists call the mantle, and it is this which by slow degrees secretes and supplies the shell. In some species the shell is of one piece, and is called univalve; in others the shell is double, the two parts being united by a hinge; this is called bivalve. The snail is a univalve, the oyster or clam a bivalve. Other shells, on account of their structure, are called multivalve. Many shells, as that of the oyster, are deposited in layers, a fine membrane interposing between each layer; they are therefore called membraneous shells. Most membraneous shells are lined with a brilliant enameled substance, called nacre; mother of pearl is the nacre of the pearl oyster. That of the fresh-water mussel is a beautiful azure. The other structure of shells is called porcellaneous, because they look like porcelain or china. The common cowry is a well-known instance of a porcellaneous shell. Some shells are so transparent as to resemble glass, and are therefore called vitreous.

Starting with these simple definitions, let us take a general survey of the field of inquiry which lies before us. We begin with the infancy of these animals, and we may remark that at this point in their lives, the various kinds of Mollusca are more alike both in appearance and habits than in after-life; the young fry of the aquatic races are, indeed, almost as different from their parents as the caterpillar from the butterfly. The analogy, however, is reversed in one respect; for whereas the adult shell-fish are often sedentary, or walk with becoming gravity, the young are all swimmers, and by means of their fins and the ocean-currents, they travel to long distances, and thus diffuse their races as far as suitable climate and conditions are found. Myriads of these little voyagers drift from the shores into the open sea and there perish; their tiny and fragile shells become part of a deposit that is forever increasing over the bed of the deep sea, at depths too great for any living thing to inhabit.

Some of these little creatures shelter themselves beneath the shell of their parent for a time; many can spin silken threads with which they moor themselves, and avoid being drifted away.

They all have a protecting shell, and even the young bivalves have eyes at this period of their lives to aid them in choosing an appropriate locality. After a few days, or even less, of this sportive existence, the sedentary tribes settle down in the place they intend to occupy during the remainder of their lives. The tunicary cements itself to rock or sea-weed; the ship-worm adheres to timber, and the pholas and lithodomus to limestone rocks, in which they soon excavate a chamber which renders their first means of anchorage unnecessary. The mya and razor-fish burrow in sand or mud; the mussel and pinna spin a byssus; the oyster and spondylus attach themselves by spines or leafy expansions of their shell; the brachiopoda are all fixed by similar means, and even some of the gasteropods become voluntary prisoners, as the hipponyx and ver

metus.

Other tribes retain the power of traveling at will, and shift their quarters periodically, or in search of food; the river-mussel drags itself slowly along by protruding and contracting its flexible

foot; the cockle and trigonia have the foot bent, enabling them to make short leaps; the scallop swims rapidly by opening and shutting its tinted valves. Nearly all the gasteropods creep like the snail, though some are much more active than others; the pond-snails can glide along the surface of the water, shell-downward; the nucleobranches. and pteropods swim in the open sea.

THE POULPE OR CUTTLE-FISH.

The cuttle-fishes have a strange mode of walking, head-downward, on their outspread arms; they can also swim with their fins, or with their webbed arms, or by expelling the water forcibly from their branchial chamber; one species of calamary can even strike the surface of the sea with its tail, and dart into the air like the flying-fish.

By these means the mollusca have spread themselves over every part of the habitable globe; every region has its tribe, every situation its appropriate species; the land-snails frequent moist places, or woods, or sunny banks and rocks, climb trees, or burrow in the ground. The airbreathing limneids live in fresh water, only coming occasionally to the surface; and the auriculas live on the sea-shore, or in salt marshes. In the sea each zone of depth has its molluscous fauna. The limpet and periwinkle live between tide-marks, where they are left dry twice a day; the trochi and purpuræ are found at low water among the sea-weed; the mussel affects muddy shores; the cockle rejoices in extensive sandy flats. Most of the finely-colored shells of the tropics are found in shallow water, or among the breakers. Oyster-banks are usually in three or four fathom water; scallop-banks at twenty fathoms. Deepest of all the terebratulæ are found, commonly at fifty fathoms, and sometimes at one hundred fathoms, even in polar seas. The fairylike pteropoda, the oceanic snail, and multitudes of other floating molluscs, pass their lives on the open sea, forever out of sight of land; while the lisiopa and scyllaea follow the gulf-weed in its voyages, and feed upon the green delusive banks.

The food of the mollusca is either vegetable, infusorial, or animal. either vegetable, infusorial, or animal. All the land-snails are vegetable-feeders, and their depredations are but too well known to the gardener and farmer; many a crop has been wasted by the ravages of the small gray slug. They have their likings, too, for particular plants: most of the pea-tribe and cabbage-tribe are favorites, but they hold white mustard in abhorrence, and fast or shift their quarters while that crop is on the ground. Some, like the cellar-snail, feed on cryptogamic vegetation, or on decaying leaves; and the slugs are attracted by fungi, or any odorous substances. The round-mouthed sea-snails are nearly all vegetarians, and are consequently limited to the shore and the shallow waters in which sea-weeds grow. Beyond fifteen fathoms, almost the only vegetable production is the nullipore; but here corals and horny zoophytes take the place of alge, and afford a more nutritious diet.

The whole of the bivalves, and other headless shell-fish, live on infusoria, or on microscopic vegetables, brought to them by the current which their ciliary apparatus perpetually excites; such, too, must be the sustenance of the magilus, sunk in its coral bed, and of the calyptræa, fettered to its birth-place by its calcareous foot.

The carnivorous tribes prey chiefly on other shell-fish, or on zoophytes, since, with the exception of the cuttle-fishes, their organization scarcely adapts them for pursuing and destroying other classes of animals. One remarkable exception is formed by the stylina, which lives parasitically on the star-fish and sea-urchin; and another by the testacelle, which preys on the common earth-worm, following it in its burrow, and wearing a buckler, which protects it in the rear. Most of the siphonated univalves are animal-feeders; the carrion-eating stromb and whelk consume the fishes and other creatures whose remains are always plentiful on rough and rocky coasts. Many wage war on their own relatives, and take them by assault; the bivalve may close, VOL. II.-62