stairs. Each trough is three feet in length, seven inches in width, and five in depth. It is found, however, that the depth need not exceed four inches. In these troughs is placed a layer of moderately fine gravel, about two inches in depth, and larger stones are stuck into the gravel at intervals of an inch or two. The gravel and stones have been previously boiled and washed, in order to destroy all traces of decaying animal matter which might taint the water, all aquatic creatures which might injure the eggs or fry, and all confervoid growths which might choke up the stream and interfere with the wellbeing of the young fishes.

Above these troughs is placed a large tank holding about two hundred gallons of water, which is conducted to the upper trough by means of a pipe and stopcock. At alternate ends of each trough is placed a short pipe which conveys the water from one to the other, and in consequence of their alternate arrangement compels the water to traverse the entire surface of the gravel.

The eggs are carefully laid upon the gravel so as to lodge in its interstices, each trough containing three thousand ova. As, therefore, the percentage of unhatched eggs is extremely trifling when they are in proper condition, this single set of troughs can turn out about thirty thousand young fish at a single hatching.

HATCHING-PLATE.

An experiment has been successfully tried to substitute slabs of slate for the gravel, the plates being exactly one foot long and seven inches wide, so that three will precisely fit into each trough. The

plates are covered with cup-like hollows, much resembling the little pits in a solitaire' board: a small hole is pierced quite through the centre of each, so as to permit water to pass freely. Each plate contains one thousand of these cups, and each is intended to hold one egg, so that the tedious process of counting the ova is no longer required.

When the eggs are properly arranged, the water is permitted to flow very gently over them, and its force is gradually increased until it imitates as nearly as possible the shallow rippling part of the stream where the fish generally lays its eggs, and the motion of which seems to be essential to the hatching of the egg. The stream is about one inch in depth.

One great advantage of this plan is, that the eggs and young are always kept in view, and are at a convenient height from the ground, so that they can be watched with a lens through the crystalline water, and their changes noted from day to day.

Another establishment is placed in the open air, not very far from the banks of the Thames. This consists of a series of flat troughs made of elm, and measuring four feet in length, fifteen inches in width, and eight in depth. These troughs or boxes are furnished with gravel and stones, as has already been mentioned: they are set end to end, and water flows continually through them from a little spring which has been ingeniously diverted in the proper direction.

The eggs are placed in the upper boxes, covered with coarse gravel, and the water suffered to flow gently over them, until they are hatched, an event which usually takes place in sixty or seventy days. The temperature of the water has, however, much to do with the time occupied in hatching. In this establishment, where the water is kept at a tolerably uniform temperature of 45° Fahr., the commencement of the process is visible in fifty-five days, the action of the heart being perceptible even to the naked eye, and a most beautiful object under the microscope.

When first hatched, the young fish is a most curious little object, having

a thin, long, transparent body, hardly visible when immersed, and bearing the yolk of the egg attached to its abdomen. This egg vesicle is of a

EGG, FRY, AND PARR.

bright reddish orange colour, traversed by the minutest imaginable vessels of bright scarlet, and remains visible for about seven weeks. As long as the little creature retains

this vesicle it needs no food, and takes no trouble about feeding until it has lived for seven or eight weeks, when the supporting vesicle is absorbed into the body, and the fish is then thrown on its own energies for subsistence.

Now comes a critical time in the life of a fish, and one where many pisciculturists have failed. What is the little creature to eat, and how is it to obtain its food? Liver, dried and reduced to powder, is held in some estimation, and so are little worms and caddis chopped very fine. Stale bread grated into a fine powder is another useful kind of food. But it often happens that the little fishes are so delighted with the un

the perfect shape and begin to feel the want of food. This food they will then find for themselves. The sharp-eyed little creatures can see and capture the myriad tiny inhabitants of the water which are too minute to be detected by the human eye, and when they get a little stronger may be seen jumping at midges with wonderful boldness and activity.

Their peculiar habits are a sufficient guide to their owner as to the time when they are fit to enter the river and be turned loose on existence, for they drop down from box to box according to their development, and those that are found in the lowest box are always strong enough to be removed.

It should be mentioned that gratings of perforated zinc form an impassable obstacle to the escape of the young fish or the entrance of obnoxious intruders, while covers of the same substance are fastened over them at night, and are replaced in the daytime by strong netting. The object of this change is twofold: firstly, that the midges and other little insects on which the fish feed should have free admission to the surface of the water; and secondly, that the inmates should be guarded from various predatory birds, kingfishers especially, who would hold high revel over so plentiful and delicate a banquet.

When the fry have attained a moderate size, they are removed from the lowest box, placed in a proper water vessel, and transferred to a boat. The owner rows gently about the river, and wherever he sees a favourable looking spot he puts a hundred or so young fish into the water. No sooner are they in the river than they act as freely and boldly as if they had passed all their little lives in its stream, dive down at once, and ensconce themselves among the pebbles. This instinct is most valuable, as the fish know by its wondrous power how to separate from each other, and take up their abode in little nooks and crannies, where not even the voracious perch can get at them-at all events, not without an expenditure of labour which that fish is not at all likely to employ.

The plan of putting them into the river in little detachments is followed because it is found that whenever the little fish are thrown into the water wholesale, the larger river fish make a great feast on their little visitors, charge fiercely at the crowd, and more than decimate their ranks before they can conceal themselves, their very numbers preventing them from finding the shelter which their instinct urges them to seek.

They are very pretty, these little fish, and even in their very young days possess sufficient individuality to mark each species. The young salmon fry, for example, are rather long and slender in proportion to their width, and their hue is ruddy brown, barred with dark patches on the sides. The young trout are shorter, thick and dark, and the barred surface is perfectly conspicuous even when the little creatures do not measure one inch in length. The char are light gray above and silvery white beneath, and have a peculiar darting action, flashing through the water like a miniature rocket, and just turning on the side so as to suffer a silvery gleam to appear for a moment and then vanish.

The eggs are delicate globular bodies, varying in size according to the species of fish from which they come. Those of the salmon are about the size of sweet peas, and the perfect, healthy, and vivified egg has a peculiar translucency, with pink or ruddy reflections as the light passes through its substance.

As the eggs approach maturity the blood-red hue deepens, and when the little fish makes its escape from the imprisoning envelope the egg vesicle retains its warm hue. Indeed, it is only by this vesicle that the presence of the very young fish can be detected as they lie among the stones, the delicate bodies being of such glassy transparency that they would escape observation but for the ruddy hue of the egg vesicle which is attached to them.

Should the egg be unfortunate, and its vital principle escape, the fatal result may be at once known

by the change of aspect, a gradually increasing opacity spreading through the whole substance, and the egg looking exactly like a boy's alley taw' seen through the wrong end of a telescope. By degrees a kind of flocculent excrescence begins to grow upon the egg, and it is soon surrounded with this growth to such an extent that it becomes as large as a moderately-sized gooseberry. All such eggs must be removed from the water, or they would otherwise taint its purity; and as the increased bulk renders them lighter than the element in which they lie, they float to the surface and are readily detected.

Whether the eggs are hatched sooner in the artificially made gravel beds of the troughs than in the natural gravel of the river is not very clear, but it is certain that even in the open-air boxes, where all conditions are apparently identical, the salmon eggs are hatched in little more than half the time which the generality of books mention as necessary for that operation. It is hardly needful to say that the rapidity of hatching is an important element in pisciculture, and that the breeding apparatus is rendered more valuable in proportion to the number of hatchings of different fish it can turn out in a season. After each hatching it is as well to remove the gravel, wash the troughs thoroughly, and not to replace the stones and gravel until they have again been submitted to the ordeal of boiling water.

The question of mixed or hybrid breeds is now attracting considerable attention, and many thoughtful inquirers are endeavouring to produce mixed breeds of fish just as enterprising agriculturists produce. breeds of cattle. It seems to have been tolerably well proved that with trout the surest method of obtaining the heaviest and finest fish is to introduce continual additions of new blood into the establishment, so that the dwindling process which generally happens when the in and in' system is adopted may be obviated, and a fine and healthy offspring be

the result.

Some experimentalists have mooted another question, namely, the possi

bility of crossing the salmon with some other fish, so that the offspring may retain the size, flavour, and beauty of the salmon, while the migrating instinct may be eradicated. I do not think, however, that any such attempt can be successful. In all the history of cross breeding the results prove that it is always possible to introduce an instinct, but that to eradicate one is a task almost if not quite impossible. The outward form may be alterable to any extent, but the inward character will remain.

In the greyhound, for example, when the breed was found to gain speed at the expense of courage and endurance, relinquishing their quarry at the first check, a cross of the bulldog was introduced. In a few generations the clumsy head and short limbs of the bulldog were eradicated, but the indomitable courage and tireless perseverance have remained, and the result is the present breed of greyhounds, which will not only run like the wind, but are marvellously enduring, and when they have once been set on the track will continue the chase until they drop from fatigue, or even die on the spot. Taking these and other similar examples into consideration, I cannot but think that the result of crossing the migratory salmon with some stationary species would have precisely the opposite effect to the intentions of the pisciculturist, and that, instead of making the migrator stay at home, the cross would only send the non-migrator off to sea.

Moreover, to obtain a hybrid by means of crossing two distinct species of fish is a very different business from getting a mixed breed of varieties belonging to the same species of cattle. And although it is true that even in the wide seas specimens are now and then caught which possess the characteristics of two separate species in such equal proportions that they cannot be referred with certainty to either, yet these exceptional cases prove little but a fact already known; and though they show that hybrid or mule fishes can be obtained, they fail to demonstrate any advantages to be gained by them.

We have said nothing as yet with respect to the means by which the eggs are obtained by the pisciculturist. It is, of course, necessary to be perfectly sure of their genuineness, and the only method by which this question can be decided with absolute certainty is to procure them from the parent fish.

Nothing is simpler than this process. At the spawning time, just when she is about to deposit her eggs, the female fish is put into a tub with water, and by a little artificial aid the whole of the eggs, or 'hard roe,' are soon laid in the tub. The fish is then released, and suffered to return to her native river. A male fish of the same species is then put into the same vessel, and some of the milt, or 'soft roe,' is deposited in a similar manner. He is then set at liberty, and the water stirred about for a few minutes, when it becomes cloudy, as if milk had been poured in it, but soon regains its former clearness. The eggs are then rinsed with fresh water, and are fit to be put into the trough.

Indeed, the whole process of hatching the fish is so simple and easy that it may be achieved with a flower-pot and a watering-can, and conducted on a drawing-room table. Any one can do it, and it is really so elegant and interesting a process that it may possibly become as fashionable as the ferneries and aquaria of the present day.

Vivified eggs can now be readily procured from many parts of England and some portions of the Continent. For the little establishment already mentioned the eggs of trout have been brought from the Teste and Bourne in Hampshire, from the Colne in Herts, and the Wandle in Surrey. Salmon ova have been obtained from several parts of Ireland, as well as from the Rhine, the char have come from Geneva, and the grayling been taken from several British rivers where this delicate and beautiful fish survives. Eggs can be safely conveyed, if packed carefully in wet moss and placed in wooden boxes.

It will always be found advisable to make provision in various parts of the river which is intended to be the future residence of the young fish,

not only for their youthful, but their adult state. Several fish, such as trout, pass solitary lives, each choosing some particular haunt, and only changing its residence when it has outgrown its home or can oust a weaker fish from some comfortable nook.

The trout loves to lie under the shelter of large stones, and if a good artificial place of refuge can be made, the best fish are sure to come and take possession of it. Perhaps the very best substance for this purpose is the semi-vitrified brick which is found in kilns after the burning, and which goes by the name of brickburrs. This substance is in rather large masses, very irregular, and not only affords a home which no sensible trout will despise, but is an effectual barrier to the use of the net, serving the same purpose in the river as 'bushing' in the open fields.

Feeding the trout is also useful, for it teaches the fish to remain near the same spot, and has a marvellous effect towards increasing its growth. Scarcely any creature, and certainly no fish, repays care and good feeding better than the trout, two pounds having been added to the weight of a fish during a single summer. When the trout attains a moderate size it will eat all kinds of animal substance, though it has a predilection for the great dew-worms that are found at night on the grass or gravel walks.

These great, fat, and wary creatures can be caught plentifully by searching for them at night by the aid of a bull's-eye lantern; only the step of the hunter must be very quiet, as they are apt to slip back into their holes if alarmed. Should they not come readily to the surface, they may usually be induced to do so by driving the prongs of a gardenfork into the ground and working it about so as to shake the earth around; and if they still should be obdurate, they may be brought to light by pouring over the ground some water in which a very little ammonia has been dissolved.

Not only the river fishes, but those of the salt water can be reared from the earliest stages, and kept in ponds