. The elements of experimental embryology. Embryology, Experimental; Embryology. Fig. 221 Regional inductive powers of exogastrulated organiser, a, diagram showing experiment of placing pieces of undetermined epidermis on the anterior (i), middle (2), and posterior (3) regions of the organiser (chorda-mesoderm) of exo-embryo of axolotl. b, tail induced from epidermis in position 3. (From Holtfreter, Biol. Zentralbl. liii, 1933.) A further set of important experiments was made by taking un- determined ectoderm from normal early gastrulae and laying it on different regions of the chorda-mesoderm
. The elements of experimental embryology. Embryology, Experimental; Embryology. Fig. 221 Regional inductive powers of exogastrulated organiser, a, diagram showing experiment of placing pieces of undetermined epidermis on the anterior (i), middle (2), and posterior (3) regions of the organiser (chorda-mesoderm) of exo-embryo of axolotl. b, tail induced from epidermis in position 3. (From Holtfreter, Biol. Zentralbl. liii, 1933.) A further set of important experiments was made by taking un- determined ectoderm from normal early gastrulae and laying it on different regions of the chorda-mesoderm of the exogastrulated endo-mesoderm in the exogastrulation experiments. This must be done in early stages, before the presumptive chorda-mesoderm has disappeared under the surface of the endoderm (see fig. 221). The results are striking. From whatever presumptive region the pieces of ectoderm were taken, they differentiate in accordance with the regional properties of the organiser on which they are lying. If placed on the anterior (head-organiser) part of the. 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
