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. The elements of experimental embryology. Embryology, Experimental; Embryology. CLEAVAGE AND DIFFERENTIATION an apical organ. It is clear, therefore, that in the egg of Dentaliiim there is a particular portion of the cytoplasm which is precociously chemo-difTerentiated, and essential for the formation of the apical organ and post-trochal region. This portion is contained in the first polar lobe, the contents of which are distributed in a definite and unequal way between the various blastomeres (fig. 53). These conclusions are confirmed by experiments (also on Denta- liiim) of a rather diflfer
. The elements of experimental embryology. Embryology, Experimental; Embryology. CLEAVAGE AND DIFFERENTIATION an apical organ. It is clear, therefore, that in the egg of Dentaliiim there is a particular portion of the cytoplasm which is precociously chemo-difTerentiated, and essential for the formation of the apical organ and post-trochal region. This portion is contained in the first polar lobe, the contents of which are distributed in a definite and unequal way between the various blastomeres (fig. 53). These conclusions are confirmed by experiments (also on Denta- liiim) of a rather diflferent kind, in which the polar lobe is simply cut oiT, without separating the blastomeres. If the polar lobe is cut off at the onset of the first cleavage, the larva (like that from isolated. 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