. The elements of experimental embryology. Embryology, Experimental; Embryology. THE HEREDITARY FACTORS AND DIFFERENTIATION 399 itself with its axis along a radius of the centrifuge, and the stratified distribution of its contents is accentuated. Further, the egg be- comes flattened, and the cleavage-spindle, adapting itself to the longest axis of available cytoplasm, lies horizontally instead of in the vertical position. The result is a cleavage division in the vertical. 2-cell taking Fig. 192 Cleavage and chromatin-diminution in the normal egg of Ascaris. i, stage. The first cleavage is lati
. The elements of experimental embryology. Embryology, Experimental; Embryology. THE HEREDITARY FACTORS AND DIFFERENTIATION 399 itself with its axis along a radius of the centrifuge, and the stratified distribution of its contents is accentuated. Further, the egg be- comes flattened, and the cleavage-spindle, adapting itself to the longest axis of available cytoplasm, lies horizontally instead of in the vertical position. The result is a cleavage division in the vertical. 2-cell taking Fig. 192 Cleavage and chromatin-diminution in the normal egg of Ascaris. i, stage. The first cleavage is latitudinal; chromatin-diminution is place in the animal cell. Si(AB), first somatoblast rudiment of the primary ectoderm. la, Enlarged view of the diminution process. 2, 3, 4-cell stage; 2, T-shaped phase. 3, Lozenge-shaped phase. Note extra-nuclear chromatin resulting from diminution in A and B. S.^ {EMSi), second somatoblast (endo- meso-stomodaeal rudiment). 4, At the next cleavage, chromatin-diminution occurs in the second somatoblast. 5, 6, Later stages. iSj, secondary and tertiary ectoderm rudiments. P4, germ-cell with undiminished chromatin. (After Boveri, from Jenkinson, Experimental Embryology, Oxford, 1909.). 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
