. Anatomischer Anzeiger. Anatomy, Comparative. 551 conspicuously related to a marked polarization of the chromosomes their focus being represented by the centrosomes and archoplasm taken together. In the cells after the penultimate division, the archoplasm is only conspicuous by its absence, its disappearance being directly connected with an extrusion of the entire spindle — or rather intra-zonal — fibres as a fusiform mass between the daughter cells (Fig. II). In the centre of this mass there are to be found 3—6 small chromatic particles arranged as an equatorial transverse band (fig. 26), co
. Anatomischer Anzeiger. Anatomy, Comparative. 551 conspicuously related to a marked polarization of the chromosomes their focus being represented by the centrosomes and archoplasm taken together. In the cells after the penultimate division, the archoplasm is only conspicuous by its absence, its disappearance being directly connected with an extrusion of the entire spindle — or rather intra-zonal — fibres as a fusiform mass between the daughter cells (Fig. II). In the centre of this mass there are to be found 3—6 small chromatic particles arranged as an equatorial transverse band (fig. 26), conspicuous only when the mass intervening between the cells is of considerable length. The chromatic particles of which it is composed have all the appearance of being the unclaimed central moiety of the chromosomes at the points of their division (fig. 3&) and they thus possess a striking similarity to certain bodies described by Boveri in connection with a possible reduction process in the embryos of A scar is1). At the same time it can hardly be doubted that they are equally homologous with the "intermediate body" described by Flemmino. If they are so, however, the homology he claimed between these bodies and the cell plate of plants and the lower orders of animals, seems to me to vanish; be- cause, so far as I am aware, where this structure exists it is always the fore- runner of the divi- sion wall of daughter cells, while the little chromatic particles are quite indepen- dent of the formation of a new bounding membrane in the cells of ScyIlium. Round the daugh- ter nuclei formed by the penultimate division, are a number of small chromatic masses, found on examination to be intimately related to a vacuolation of the cyto-. III. 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 Anatomisc
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