On the nucleus of the animal and vegetable "cell" / / by Martin Barry.

  • Martin Barry
Date:
1847
Catalogue details

Licence: Public Domain Mark

Credit: On the nucleus of the animal and vegetable "cell" / / by Martin Barry. Source: Wellcome Collection.

    13/36 page 211
    of the same process effects a doubling in the num¬ ber of the cells, until a mulberry-like body has 21* arisen, consisting entirely of cells ; in the centre of which mulberry is found a cell having the same general appearance as the rest, but of larger size,—a sort of queen bee in the hive. The nucleus of this larger cell is the rudimental embryo. And in the development of this nucleus into the embryo, the first discernible changes are of the same kind as those exhibited by the nucleus of every cell subsequently developed from it, and entering into the formation of the embryo. From what I have already stated, it will be seen that the twin cells in fig. 19 are endowed with qualities resulting from the fecundation of the germinal vesicle, their parent-cell; such endowment of the young cells being referable to self¬ division, effected by a process of assimilation. The reproduction of the cell is thus essentially fissiparous, its contents undergoing division after having been assimi¬ lated to the nucleus; which nucleus, therefore, it is that is reproduced,—this nucleus being a portion of the remarkable substance, hyaline, the reproduction of, or assimilation by, which seems to be a main purpose for which cells are formed. Briefly recapitulating,—the hyaline, by a very elaborate pro¬ cess, assimilates new matter, and is reproduced by division. Through successive divisions of this substance, properties descend from cell to cell,—new properties being continually acquired as new influences are applied ; but the original con¬ stitution of the hyaline not being lost. (And why do nuclei continue for a while at the surface of their cells, but for a purpose analogous to that for which the germinal spot or nucleus continues, up to a certain period, at the surface of its cell in the ovum X) I conceive that what is seen taking place in the manner here referred to,—first in the germinal vesicle, and then in the individual cells, the descendants of this vesicle,—is es¬ sential to what we observe in the reproduction of the entire organism, namely, a mysterious reappearance of the qualities of both parents in the offspring; manifesting itself, as this
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