. The cell in development and inheritance. Cells. CRITIQUE OF THE ROUX-WEISMANN THEORY 407 E. Critique of the Roux-Weismann Theory - It is impossible not to admire the thoroughness, candour, and logical skill with which Weismann has developed his theory, or to deny that, in its final form, it does afford up to a certain point a formal solution of the problems with which it deals. Its fundamental weakness is its ^//^?j-/-metaphysical character, which, indeed, almost places it outside. C D Fig. 183. — Half and whole cleavage in the eggs of sea-urchins. A. Normal sixteen-cell stage, showing the f
. The cell in development and inheritance. Cells. CRITIQUE OF THE ROUX-WEISMANN THEORY 407 E. Critique of the Roux-Weismann Theory - It is impossible not to admire the thoroughness, candour, and logical skill with which Weismann has developed his theory, or to deny that, in its final form, it does afford up to a certain point a formal solution of the problems with which it deals. Its fundamental weakness is its ^//^?j-/-metaphysical character, which, indeed, almost places it outside. C D Fig. 183. — Half and whole cleavage in the eggs of sea-urchins. A. Normal sixteen-cell stage, showing the four micromeres above (from Driesch, after Selenka). B. Half sixteen-cell stage developed from one blastomere of the two-cell stage after killing the other ' by shaking (Driesch). C. Half blastula resulting, the dead blastomere at the right (Driesch). D. Half-sized sixteen-cell stage of Toxopneustes, viewed from the micromere-pole (the eight lower not shown). This embryo, developed from an isolated blastomere of the two-cell stage, segmented like an entire normal ovum. the sphere of legitimate scientific hypothesis. Save in the maturation of the germ-cells ("reducing divisions"), none of the visible phenom- ena of cell-division give even a remote suggestion of qualitative divi- sion. All the facts of ordinary mitosis, on the contrary, indicate that the division of the chromatin is carried out with the most exact 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 Wilson, Edmund B. (Edmund Beecher), 1856-1939. New York Macmillan
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectcells, bookyear1906
