Fish culture in ponds and other inland waters by Meehan William Edward 1853-

Author:Meehan, William Edward, 1853- [from old catalog]
Language: eng
Format: epub, pdf
Tags: Fish culture
Publisher: New York, Sturgis & Walton company
Published: 1913-03-25T05:00:00+00:00

Egg Development. —After a lapse of from ten to twelve hours, a perfectly fertilised brook trout egg, when held to the light, shows what appears to be several globules not unlike air bubbles crowded about the micropyle. They are so small that only the sharp eyes of an expert can detect them, a microscope being necessary to aid the sight of the unskilled. In addition, the egg has a delicately coloured, clear, translucent appearance. After a lapse of three or four days these globules become elongated, and otherwise change to somewhat the form of the spreading roots of a tree. About a week or ten days later, the globules have disappeared and in their place there is a very indistinct outline of a little fish.

Growth of the Embryo. —Day by day the outlines grow more definite, yet only to be detected by a sharp and practised eye, until, when the egg is from eighteen days to three weeks old, two intensely black spots set close together are plainly visible. These are fish's eyes,—the first unmistakable view of the embryo observable.

Next is sharply outlined a jetty V, the two points of which touch the eyes. These converg-

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