Appearance

After the eggs have lain in the water from fifty to seventy-five days, according to the temperature, the Trout will begin to make their appearance, the egg appears to be endowed with life, and the motions of the Trout inside "kicking" against the shell to force their way out can be planily perceived without the use of a microscope. At length the Trout forces his way through, head first or tail first, those that hatch head first always dying however, and the useless shell floats away down stream. The Trout is then about one-half inch long, and the body proper as thin as a needle ; the most prominent features being a pair of eyes, huge in comparison with the rest of the body, and a sac nearly as large as the egg. This sac is attached to the belly of the fish, and contains food, which the fish gradually absorbs. If the fish are hatched in fifty days the sac lasts about thirty, if in seventy days, about forty-five. At this period of their lives they will work down into the crevices of the gravel and along the sides of the troughs and stay there, nature seeming to give them the instinct at this weak and defenceless period of their lives, when they are burdened with a load which they can hardly carry, to get out of sight and out of the way of harm as much as possible. At this stage of their growth many curious deformities appear. more interesting perhaps to the physiologist than to Trout culturist. Some of the fry will have two heads, and some will be united after the manner of the Siamese Twins. A very common deformity is a crook or bend in the Trout, giving it a semicircular form, so that when it attemps to swim it can only progress in small circles. All the deformed soon die, and may as well be removed from the trough at once. They live as long as the sac supplies them with food ; when the sac is exhausted they cannot swim about to get food, and die of starvation.

This instinct of hiding will make the young fry very uneasy if they are placed in a trough without gravel. They will keep continually in motion, or will crowd upon one another in masses each trying to work his way out of sight under the others. They must now be watched, and carefully moved from time to time if there is danger of their smothering.

Nursery

The most critical period in the life of a Trout commences when the umbilical sac is absorbed. More, perhaps die from the time they begin to feed until they are six months old, than at any other time. In consequence many different plans for nurseries have been suggested and used. The fry require a largely increased supply of water, but where only a moderate number is to be raised, in place of erecting other and wider troughs or boxes for nurseries, the better plan is to put only a few eggs, say five hundred, into each square or nest of the hatching trough. The square is then large enough with the water raised to keep the Trout well for a month or two after they commence feeding, when they may be transferred into the first or upper pond. This plan economizes space, saves one removal, and the fish do better after a month or two in the ponds than they would in troughs or rearing boxes. It is better to remove the gravel from the troughs as soon as the fish commence feeding, because then the troughs can be kept clean more easily, else particles of food will lodge in the gravel, whence they cannot be removed. The water must be raised by the cross-strip before mentioned as soon as the eggs hatch out. It would be well to fix a small screen in each alternate cross-strip, which can be done by cutting out a space of eight inches by two, and nailing a fine screen over the opening. This will prevent the Trout from running up and down in the troughs, and inconveniently crowding together.

The fry are removed from the troughs into the pond by the use of a small net, such as described among the implements of the fish raiser. Take them upon this, a few at a time, and put them in a pan of water; they will swim off the net and you may draw it from under them. In the pan they may be carried, a thousand at a time, to the pond in which you wish to place them. Put them into still water; they will settle down on the bottom and remain there for some hours, then they will begin to explore their new quarters, and in a few days will become thoroughly habituated to the place.

Boards are sometimes placed over the outer edges of the preserves to give the fish a hiding place and shelter from the sun when they wish it, and more important than all, to act as a trap tor minks in case there is danger of these destructive creatures getting into the ponds; as the boards project nine or ten inches from the sides, it a mink gets in he cannot make his way out.

Where a large number of try are hatched they have to be left in the troughs until they can be distributed, which is done as soon after the absortion of the a possible. In this case the troughs must have all the gravel removed and must be kept scrupulously clean. A very little decayed meat will render the water offensive and produce disease. This offensiveness does not show itself in the least in the appearance of the water, which to the eye may be as bright, clean and sparkling as ever. It can, however, be often detected by the smell. When gravel has been for some time in the tanks or troughs where fish are fed - even with the utmost care, if a hand-full is taken up it will be found to be very offensive to the olfactories. As well might we expect the human race to be healthy in foul atmosphere, as fish to be healthy in foul water. In the ponds it will sometimes answer to cover up or deoderise the feculent matter by throwing earth mixed with a very little salt into the water and allowing it to settle; this not only covers the decaying substances but disinfects them in a measure, on the principle that dry earth is used in the earth closet. The water is to be made quite thick and muddy with the earth, and the operation is to be renewed every few days, as often as necessary. The roiliness of the water does not seem to injure the fish. This, however, at best is but a makeshift, and the true plan, especially with young fry is to keep the troughs clean.