. The elements of experimental embryology. Embryology, Experimental; Embryology. â 3^. Fig. 178 Persistent gradient-fields affecting feather-growth in adult birds. In all, the ordinates represent growth of regenerating feathers per day. The abscissae represent distances within the breast-region, in A and C antero-posteriorly, in B and D ventro-dorsally. A, In a capon (® single feathers, (^ means). B, In a cock, in two regions of the breast. C, In a capon. D, In a cock and a hen. (Based on data of Juhn, Faulkner and Gustavsen, from Huxley, Problems of Relative Grozoth, London, 1932.) mathemati
. The elements of experimental embryology. Embryology, Experimental; Embryology. â 3^. Fig. 178 Persistent gradient-fields affecting feather-growth in adult birds. In all, the ordinates represent growth of regenerating feathers per day. The abscissae represent distances within the breast-region, in A and C antero-posteriorly, in B and D ventro-dorsally. A, In a capon (® single feathers, (^ means). B, In a cock, in two regions of the breast. C, In a capon. D, In a cock and a hen. (Based on data of Juhn, Faulkner and Gustavsen, from Huxley, Problems of Relative Grozoth, London, 1932.) mathematically as the logarithmic spiral. Slight departures from a straight-line growth-gradient give rise to departures from strict logarithmic-spiral form. The most important of such departures is seen in Molluscs. The growing edge of the mantle here makes a more or less circular aperture. If growth is equally graded on the two sides of this aperture between high and low point of growth-activity, the shell produced is a plane spiral, as in Ammonites or Scaphopods. If, HEE 24. 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 Huxley, Julian, 1887-1975; De Beer, Gavin, Sir, 1899-1972. New York [Hafner Pub. Co. ]
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Keywords: ., bookcentury1900, bookcollectionbiodiversi, booksubjectembryology
