Volume 1

Elements of physiology : for the use of students, and with especial reference to the wants of practitioners / Tr. from the German, with additions by Robert Willis.

  • Rudolf Wagner
Date:
1841-2
Catalogue details

Licence: Public Domain Mark

Credit: Elements of physiology : for the use of students, and with especial reference to the wants of practitioners / Tr. from the German, with additions by Robert Willis. Source: Wellcome Collection.

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

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    tissue {Repert. 245, Langenbeck, de Retina, 38). Schwann gave undoubted com- pleteness to these analogies when he showed that the gelatinous primdidial mass of the tissues was composed of cells, that the granules or bodies embedded in it are nuclei, and that these often exhibit laws of evolution of the same kind as the cells (Frorieps, Neue Notizen, Heft i. 3, 1838, and Micros. Unlersuch. iiber. Ein- stimmuny, &c.) In 1837, I had observed the cells of the germinal membrane in the ovum of the Sepia, with their nuclei and nucleoli, and the areas that surround them, and made known my observations in a letter to Breschet. Very shortly after I became acquainted with Schwann's first paper (Frorieps, iV. N. 1838), I began a series of observations on the subject; and the chief results of these my more recent investigations form the matter of the following communication. I have at the same time referred at the proper places to Schwann's Inquiries (Untersuchungen, &c.), the first part of which I have this day received. As among vegetables so among animals we find granular nuclei, including one or more nucleoli and surrounded by more or less independent cells, which consist of separate bounding parietes, and distinct contents. From this prim- ordial formation proceed all the tissues, how heterogeneous soever they appear in their completely elaborated and perfect estates. The different ways by which the metamorphosis happens are susceptible of arrangement in an ascending series, under the following elementary types :— I. The nuclei with their nucleoli, which at an earlier stage are free, surround themselves with a clear cell, which however soon dissolves, so that the nuclei swim about as characteristic corpuscules in the fluid, and there and as such advance in their individual development. In the normal organism this is what happens in regard to the B/ooc?, and probably also to the Lymph. The blood-globules are not cells, but nuclei. Their nuclei are in eflfect nucleoli. This view is vouched for by two decisive facts:—1. In the larvae of frogs we see plainly round or square shaped granules, applying themselves around the nucleoh {Enwickelungs- gesch. 297. Wagner, Beitr'dge, Heft ii. 38), and by and by transforming them- selves into a homogeneous shell, whilst the nucleus remains. This is the type of the mode in which the nucleus universally originates, and attains its develop- ment, whilst the cell around the nucleus appears without exhibiting any transi- tion-stage of the kind. 2. When the blood-globules of the embryo, even after they have attained the flatness that characterizes them in the mammalia, and agree in size with those of the mature animal, are treated with acetic acid, they suffer little or no change in form and size; whilst this acid immediately reacts in the well-known manner upon the fresh blood of the mother. The blood- globules of the embryo thrown into concentrated acetic acid first lose their colouring matter, although in a less degree than when treated with distilled water, and they retain their shell or envelope for two days or more, either crisped or altogether unaltered. Now insolubility in acetic acid is a general character of the nuclei of the blood-globules, whilst the cells and the products of their meta- morphoses are universally attacked in a greater or less degree by the acid in question. The bodies called the lymph-granules of the blood, are in all proba- bility free nucleoli, which gradually surround themselves with nuclei. Among the products of pathological states, exudation corpuscules [coagulable lymph granules] belong to this category. Like so many embryonic nuclei these are round, granular, and lie tessellated one upon another, whilst their very small interstices contain a transparent gelatine. Should the exudation become puru- lent, this gelatine acquires fluidity, and the pus globules then swim in the liquor 13
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