. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. THYROID AND GONAD IX PLUMAGE. 225 may extend beyond the zone of melanin pigmentation; but the reverse does not occur. In control birds, the reverse does occur. This is especially clear in the shoulder feathers of Barred Plymouth Rocks, in which dark bands pass distally across the naked barbs (Fig. 3).. FIG. 3. Representative shoulder feathers from an adult Barred P. R. male, showing barring across naked barbs. This tendency of barbules and melanin pigmentation to extend together over the feathers of thyroid fed birds is espe
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. THYROID AND GONAD IX PLUMAGE. 225 may extend beyond the zone of melanin pigmentation; but the reverse does not occur. In control birds, the reverse does occur. This is especially clear in the shoulder feathers of Barred Plymouth Rocks, in which dark bands pass distally across the naked barbs (Fig. 3).. FIG. 3. Representative shoulder feathers from an adult Barred P. R. male, showing barring across naked barbs. This tendency of barbules and melanin pigmentation to extend together over the feathers of thyroid fed birds is especially marked by reason of the fact that the zone of barbules in male birds possesses a typically notched or wavy contour with which the outer edge of melanin pigment distribution perfectly coincides. It is difficult to avoid the conclusion that the effective stimuli for barbule and for melanin formation in these feathers are one and the same. There is reason, however, for believing that this is not an adequate summary of the situation. Everything that has been said about the male bird applies as well to the capon. In the latter, such decorative feathers. 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 Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual report 1907/08-1952; Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-1983. Woods Hole, Mass. : Marine Biological Laboratory
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
