Remarks on Quekett's Histology, On Kölliker's Human histology, and on the physiological importance of the nucleus of the cell / by Martin Barry, M.D.

  • Barry, M. (Martin), 1802-1855.
Date:
[1854]
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Licence: Public Domain Mark

Credit: Remarks on Quekett's Histology, On Kölliker's Human histology, and on the physiological importance of the nucleus of the cell / by Martin Barry, M.D. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    divides into many parts wliicli are smaller nuclei,—that each of these smaller nuclei lias its own investment, and that they are the deve- loping cells of authors which give origin to the spermatozoa.^ The products of the testis have, it may be presumed, their equi- valents in the ovary; and it happens that the very plate containing my drawings now referred to, of the first elements of the sperma- tozoa of a mammal, contains also drawings of the first elements of the ova of a singing bird. Equivalent Products of the Testis and Ovarium. From the plate now referred to we may, I think, draw something like the following conclusions, viz., that In the Testis. A large cell, t^'—^V, A, fills ■with nuclei, B, the inner part of each of which forms a spermatozoon, C, while the outer part becomes tlie de- veloping cell of authors, D. The head of the spermatozoon is a nucleus, E, which subsequently exhibits a nuc- leolus, F, the fecundating element. In the Ovarium. A large cell about the same size, A, fills with nuclei, B, the inner part of each of which is a young ovum, C, while the outer part becomes my ovisac,- D. The germ spot in the ovum is a nucleus, E, which subse- quently exliibits a nucleolus, F, the part fecundated. I have just mentioned an ample confirmation by K. Wagner and E,. Leuckart, of my views on the physiological importance of the nucleus of the cell. The following remark is by the same distinguished authors: It might not be without interest to reflect upon the im- portant part which the nucleus plays in the formation of the sperma- tozoa, since it is an element which is usually only important for the formation of cells, and does not participate in their subsequent meta- morphoses.—Lc. p. 501. This remark shows the existence still of views regarding the nu- cleus, quite unworthy of it. But when the authors add, concerning the said remark, This is at least the rule ; a rule, however, b}^ no means without exce])tion {lc. p. 501), they give evidence of having seen the nucleus doing something more than simply entering into the formation of the cell. They further say: We ali-eady know that in many cases the nucleus is important for the develop- ment of certain parts (Zc. p. 501), which they mention ; and they add, We know that the nucleus .... even converts itself. . . into peculiar fibrous formations—into the so-called nuclear fibres (Kei'n- lasern).^ Still more remarkable is the metamorphosis of the nucleus 1 Phil. Trans., 1841, Plate XXV., fig. 1611. It may be deserving of remark that these observations of mine were made on the elements of spermatozoa found—not in the male, but in the female—in the vagina of a rabbit killed two hours post co'Uuin. 2 The ovisac acquires a vascular covering, and there is thus formed a Graafian follicle.—Phil. Trans., 1838. 3 Vid. Henle (Allgemein. Anat. s. 193) and Zwicky (Metamorphose der Thrombus).