. Principles and practice of poultry culture . Poultry. APPLICATION OF PRINCIPLES OF BREEDING 519 secured in both cases by the application of the same prin- ciple of special mating, — breeding not the Standard- colored bird of either sex to a mate of the other sex of the same shade of color, but the male to a female of the color and breeding of his dam, and the female to a male of the color and breeding of her sire. There is, however, this differ- ence in the cases compared: when sexual differences in color are exaggerated by a standard, the application of the principle keeps apart the lines o
. Principles and practice of poultry culture . Poultry. APPLICATION OF PRINCIPLES OF BREEDING 519 secured in both cases by the application of the same prin- ciple of special mating, — breeding not the Standard- colored bird of either sex to a mate of the other sex of the same shade of color, but the male to a female of the color and breeding of his dam, and the female to a male of the color and breeding of her sire. There is, however, this differ- ence in the cases compared: when sexual differences in color are exaggerated by a standard, the application of the principle keeps apart the lines of breeding, or subvari- eties. When a standard seeks to make the sex color types identical, the application of the principle of special matings tends first to fix the types and finally to fuse the lines. Allu- sion was made to this in the paragraph relating to modified black-red types. Nowhere is the evidence of prog- ress toward fusion of sex varieties as marked as in the evolution of the Barred Plymouth Rock. From within a few years after they were estab- lished, the two lines have been steadily converging. The dark females with indistinct barring, once used in the male line, and the nearly white males with just a suggestion of barring, once used in the female line, are rarely seen now. Crosses of the two lines are occasionally. F"^' 537- Light Brahma cockerel, owned by H. B. Robinson, Reading, Massachusetts. 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 Robinson, John H. (John Henry), 1863-1935. Boston ; New York : Ginn and Company
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Keywords: ., bookauthorrobinson, bookcentury1900, bookdecade1910, bookyear1912
