. Chickens and how to raise them;. Poultry. AND HOW TO RAISE THEM 23 —say 104 degrees—for a few hours the germ- spot (Fig. 3) enlarges and elongates. It is lying- in a slight hollow on the surface of the yolk, and in about forty-eight hours the little network of blood-vessels, which are spreading out from the central spot like the fibrous roots of a tree, begin to pulsate with the movement of the blood. At this stage the embryo is surrounded by a trans-. Fig. 4.—Embryo About the Fifth Day Reference: al, Allantois parent sac, called the " amnion," but no sooner does the circulation of
. Chickens and how to raise them;. Poultry. AND HOW TO RAISE THEM 23 —say 104 degrees—for a few hours the germ- spot (Fig. 3) enlarges and elongates. It is lying- in a slight hollow on the surface of the yolk, and in about forty-eight hours the little network of blood-vessels, which are spreading out from the central spot like the fibrous roots of a tree, begin to pulsate with the movement of the blood. At this stage the embryo is surrounded by a trans-. Fig. 4.—Embryo About the Fifth Day Reference: al, Allantois parent sac, called the " amnion," but no sooner does the circulation of the blood begin than another organ of the greatest importance is de- veloped. This is the " allantois " (Fig. 4). It is a semi-transparent sac or bag, that, starting from the navel of the embryo, gradually increases in size until it entirely surrounds the contents of the egg} its extremities coming in contact with. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Johnson, A. T. [from old catalog]. Philadelphia, The Penn publishing company
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishe, booksubjectpoultry
