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

  • Barry, M. (Martin), 1802-1855.
Date:
1847
Catalogue details

Licence: Public Domain Mark

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

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    cerning which Professor Owen in a lecture remarked, “ There is a close and interesting analogy between the above pheno¬ mena, which were published in 1841, and some of those com¬ municated by Dr M. Barry to the Boyal Society, in January 1841, and published in the Philosophical Transactions of the same year. The clear central nucleus of the blood-corpuscle [see figs. 22, 23, 24, 25] is there shewn to form two discs, which give origin to two cells. We may, likewise, discern in the pellucid nucleus of the yolk, dividing and giving origin to two yolk-cells, according to the German author, the hyaline nucleus of Dr M. Barry.”* Between the appearances presented by the mammifer- ous germ during the passage of the ovum through the ovi¬ duct and certain infusoria, including the volvox globator as figured by Ehrenberg (some of whose observations have been confirmed and extended by myselff), the resemblance, first mentioned by Professor Owen, is so remarkable that we cannot avoid the belief, that the same process operates in both. And farther, we have here a most interesting confirmation of the view, that the germ of the highest animals at certain pe¬ riods, represents, or passes through forms permanent in the lowest. Cilia-bearing cylinders arise, not by coalescence—as sup¬ posed by Valentin—but by division, like some of the Vorti- cellse ; which they resemble also in the position of the cilia. I have already said that in Mammals, the rudimental em¬ bryo is no other than the nucleus of a cell; which nucleus originally has the same appearance and undergoes the same kind of changes as the nucleus of every cell subsequently de¬ veloped from it, and entering into the formation of the em¬ bryo.—The first portion of the embryo that is formed is the chorda dorsalis, corresponding to the supposed “ primitive trace” of authors. I have published a memoir* shewing this * Hunterian Lectures. 1843. P. 78. 1 See the Number of this Journal for October 1843, pp. 214-219. t Philosophical Transactions. 1841.