ARTIFICIAL PROPAGATION OF THE RAINBOW TROUT. 
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gills are affected, the flsli will usually swim liigh iu the water, and iu an uneasy rest- 
less manner, as if gasping for breath. When this is observed the gills should be 
examined to see if they are becoming intlamed and swollen. If the lish are taking a 
skin disease, they will generally indicate it by rubbing themselves on the bottom of 
the trough or against anything that may be convenient. They will dive down and 
give themselves a quick twisting motion against the bottom of the trough, as if they 
were trying to scratch a place that was itching. If the j)rogress of the disease is not 
promptly checked it will soon be at a stage when nothing can be done, and the fish 
will grow weaker every day until they begin to die iu alarming numbers. 
The best remedy for both diseases that I know of is sab. Draw the water low on 
the fish and apply it freely by sprinkling it evenly through the water. If it is a bad 
case of skin disease I would use a half pint of salt for each gallon of water in the 
trough, or about that proportion. Watch the flish closely, and let them remain in 
the salt water until they get restless and begin to turn on their sides; then turn on 
fresh water, and as the trough fills you will have the satisfaction of seeing the slime 
rise and float on top of the water, like a white scum. Coarse sand should be kept iu 
the trough for the fish to scratch themselves against. Salt will also be good for the 
diseased gills; it will free them of all sediment, etc., that is sure to adhere to them. 
Fungus, “blue swelling,” etc., sometimes occur, but I have never had any serious 
trouble with any diseases of the fry except the two first named. Parasites will 
sometimes attack the fish, but if the water is luire and the fish are in a healthy 
condition, I hardly think the parasites will give much trouble. To kee.]) the fish that 
are reared in troughs and taidis iu a healthy condition, I think it is well to give them 
a salt bath occasionally. A little salt in their food will not hurt them, and it sometimes 
seems to do them good. I consider a little sediment from the reservoir, or such as 
collects on stones, etc., iu the streams, a good preventive of disease, if mixed with 
their food; it is only natural that they should have something of that kind, since all, 
or nearly all, of their natural food contains more or less of it. 
Diseases of the adult trout . — A very serious disease, for which I know no name, 
shows the following symptoms: The afflicted fish refuse to take food, and very dark 
spots, from | to 1 inch iu diameter, appear on different parts of the body. These siiots 
vary in number from 2 or 3 up to 25 or 30 on each fish affected. A light spot about 
the size of a green pea appears ou the head immediately over the brain. The fish are 
generally restless; some will seek the shallow water in the corners of the pond or else 
hide away among the plants, if there be any iu the pond accessible to them. Within 
24 hours from the time the disease is noticeable the fish begin to die. They will jumii 
and dart around in the water, as if crazy, and then settle back on their tails and 
sink to the bottom of the pond iu their last struggle for life. Almost by the time 
they reach the bottom they are dead and stiff'. This disease made its appearance at 
the Wytheville Station in December, 1895. It was first observed among a lot of 637 
yearling Von Behr or brown trout that had been delivered to the station on November 
29 by one of the United States Fish Commission transporting cars. The first sign of 
this disease was noted about the 5th of December, and by the 12th of the month 455 
of the 637 fish were dead. These fish being in the nursery during the first stages of 
the disease, the water passed from them through an empty pond into a second one 
containing about 1,000 large rainbow trout that had recently been stripiied of their 
spawn. On the morning of December 23, this dreadful disease made its appearance 
