The Evolution of Man — Volume 1 by Ernst Heinrich Philipp August Haeckel
page 128 of 358 (35%)
page 128 of 358 (35%)
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dissolution (caryolysis), the formation of knots and loops (mitosis),
and a movement of the halved plasma-particles towards two mutually repulsive poles of attraction (caryokinesis, Figure 1.11.) (FIGURE 1.10. Blood-cells, multiplying by direct division, from the blood of the embryo of a stag. Originally, each blood-cell has a nucleus and is round (a). When it is going to multiply, the nucleus divides into two (b, c, d). Then the protoplasmic body is constricted between the two nuclei, and these move away from each other (e). Finally, the constriction is complete, and the cell splits into two daughter-cells (f). (From Frey.)) FIGURE 1.11. Indirect or mitotic cell-division (with caryolysis and caryokinesis) from the skin of the larva of a salamander. (From Rabl.). A. Mother-cell (Knot, spirema), with Nuclear threads (chromosomata) (coloured nuclear matter, chromatin), Cytosoma, Nuclear membrane, Protoplasm of the cell-body and Nuclear sap. B. Mother-star, the loops beginning to split lengthways (nuclear membrane gone), with Star-like appearance in cytoplasm, Centrosoma (sphere of attraction), Nuclear spindle (achromin, colourless matter) and Nuclear loops (chromatin, coloured matter). C. The two daughter-stars, produced by the breaking of the loops of the mother-star (moving away), with Upper daughter-crown, Connecting threads of the two crowns (achromin), Lower daughter-crown and Double-star (amphiaster). D. The two daughter-cells, produced by the complete division of the two nuclear halves (cytosomata still connected at the equator) (Double-knot, Dispirema), with Upper daughter-nucleus, Equatorial constriction of the cell-body and Lower daughter-nucleus.) |
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