. Domesticated trout [microform] : how to breed and grow them. Fish culture; Trout; Pisciculture; Truite. APPENDIX IX. 317 draw the fish slowly over the pan to the opposite edge, letting the roe fall in the water, and fasten the other end of it, as before, to that edge of the pan. You will then have the roe suspended in the water in such a way that it cannot get together and stick, and suftbcate itself, as it surely would if it had a chance. Shake the pan a little. In an hour rinse the eggs, change the water twice a day, and in twenty days, if the water is not too cold, your egf^s will hatch.
. Domesticated trout [microform] : how to breed and grow them. Fish culture; Trout; Pisciculture; Truite. APPENDIX IX. 317 draw the fish slowly over the pan to the opposite edge, letting the roe fall in the water, and fasten the other end of it, as before, to that edge of the pan. You will then have the roe suspended in the water in such a way that it cannot get together and stick, and suftbcate itself, as it surely would if it had a chance. Shake the pan a little. In an hour rinse the eggs, change the water twice a day, and in twenty days, if the water is not too cold, your egf^s will hatch. 60 degrees Fahrenheit is a very o-ood tem- perature to hatch them in, but they will stand a tempera- ture as high as 85 degrees, at which point their develop- ment is very rapid. At 95 degrees they die. If you put a couple of large stones in the pan, to rest the ends of the loe on, it is better than to stick them to the edge of the pan. The development of the perch embryo is exceedingly interesting. A very singular feature of it is the m ement of the embryo in the egg, which begins almost as soon as the form of the fish is visible. The little creature jumps from one wall of the egg to the other, with a quick spas- modic movement, like that observed in the animalculae in a drop of water under a very high magnifying power. This motion is as regular, when the eggs are not dis- turbed, as the ticking of a watch, and never ceases, day or night, except when the eggs are shaken, when, by an instinctive consent, every fish stops as if by magic. In a second or two the movement begins again. The viscous matter which envelops the eggs and holds them together is finally wholly absorbed, and the eggs fall apart. They now consist of merely a frail shell, rontain- ing the embryo. This shell easily breaks, and the young perch is set free. He is very small, not more than half as large as a black bass just hatched, or one fourth as large as a whitefish an hour old. The roe of the yellow perch co
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