. The anatomical record. Anatomy; Anatomy. DIFFERENTIATION IN NERVOUS SYSTEM 531 refinements which seem to me quite unnecessary, it is ob\'ious that "during folding there is a marked outward migration of nuclei (see text-figure 2). With this outward migration, there is associated, from the geometrical necessities of the case, a distinct increase in the volume of the outer zone. Both these changes in the folding nervous system would occur if this tissue were suitably pressed upon from without, but since the neural plate folds itself, the forces that result in the translocation of materials
. The anatomical record. Anatomy; Anatomy. DIFFERENTIATION IN NERVOUS SYSTEM 531 refinements which seem to me quite unnecessary, it is ob\'ious that "during folding there is a marked outward migration of nuclei (see text-figure 2). With this outward migration, there is associated, from the geometrical necessities of the case, a distinct increase in the volume of the outer zone. Both these changes in the folding nervous system would occur if this tissue were suitably pressed upon from without, but since the neural plate folds itself, the forces that result in the translocation of materials and the change in the shape of the cells must be sought within the autonomous system. V. THE INCREASE IN THE VOLUME OF THE NERVOUS SYSTEM DURING FOLDING Change of shape in the cells of a folding tissue may occur with constant volume. In the neural plate, for instance, the inner zones of the cells might decrease by an amount exactly equalled by the increase in the outer zones. This, however, is not true. TABLE 2 Distribution of nuclei in inner and outer zones. Inner 1 Outer Inner Outer Inner Out«r 32 31 31 25 15 40 32 21 '•>••> 42 15 45 34 24 16 34 21 52 65 ! 14 27 29 13 34 39 ' 33 IS 32 •?>••> 47 38 20 27 55 1(> 43 31 2S 33 37 26 38 33 i '^'^ 29 45 13 38 37 21 21 37 20 32 44 ' 24 24 10 32 20 35 Ave. 3S 24 37 18 39. 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 Bardeen, Charles Russell, 1871-1935, ed; Boyden, Edward A. (Edward Allen), 1886-1976; Bremer, John Lewis, 1874- ed; Hardesty, Irving, b. 1866, ed; American Association of Anatomists; American Society of Zoologists; Wistar Institute of Anatomy and Biology. [New York, etc. ] A. R. Liss [etc. ]
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectanatomy, bookyear1906
