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.

  • Wagner, Rudolph, 1805-1864.
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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    traction. The contents are not of a pure white colour, but decidedly yellowish, and the fibre occasionally exhibits a small clear (granular) nucleus in different places of its course. At a later period the fibre becomes white, and the more the sheaths are individualised, the more does it exhibit windings, and increase in breadth and thickness. IX. Finally, the earthy deposits of the body manifest their cellular relation- ships in a less obvious manner. The auditory crystals present themselves in the sheep's foetus of from six to seven inches long, as very small elongated round bodies. If a fine slice of the membranous labyrinth be examined, three or four of these crystals may be seen connected with a nucleus, like so many nucleoli. These minute bodies, even at this early period, when treated with a little nitric acid, give off an abundance of carbonic acid gas. The crystalline globules are laminated, or arranged in layers, around a nucleus (Miiller's Archiv, 1836, t. x. fig. 13), or around this and a nucleolus (Remak, Obs. Anat. et Microscop. de system, nervos. struct, tab. ii. fig. 26; Repertorium, iii. tab. i. fig. 6). From the account now given, it appears that we have an ascending series of formations, in which the types I. II. III. and IV. present perfect analogies with those that are observed in the vegetable world. Types V. and VI. are essentially modified, and appertain to the very highest grades of organic formation. Types VII. and VIII. possess the purely vegetable form only in the very earliest stages; in their perfect conditions they present no analogy whatsoever with any thing we observe in plants, in point of form. The transition stage of the cellular fibre may perhaps be found to present a certain analogy with what Mohl has described and figured in Scytonema myochrus {Ueber die Verbindung der Pfianzenzellen, 1835, tab. i. fig. 10), as also in the knotty vessels of the latex of young leaves— in Robinia pseudo-acacia, for example. The universal primitive form of every tissue is therefore the cell, which itself is preceded by the nucleus as mediate, and the nucleolus as immediate products of the formative power. Cells and nuclei seem to stand in mutual and relative opposition, so that generally, perhaps invariably, the one is evolved at the expense of the other. After these transition stadia are accomplished, the tissue attains individuality according to general character and the place it occupies in the system. During this last stage the more distant organic parts enlarge, as is distinctly seen in the cells of the epithelium, in the tubular membrane, in the pigment, the ganglionic globules, the muscular fibres, the tendinous fibres, the primary fibrous fasciculi of the nerves, and the elastic fibres ; whilst mere nuclei, such as the blood, lymph, coagulable lymph, and pus-globules remain, or suffer diminution in the course of further development. That the cellular formation also forms the basis of all the morbid, new, or heterologous formations, is made manifest by the observations of Miiller, Henle, and myself. [Vide in particular the work of Miiller, Ueber krankhafte Bil- dungen, 8fc. for an excellent translation of which into English, On the Nature and Structural Characteristics of Cancer, Sj-c. we are indebted to Dr. West. 8vo. Lond. 1839. R. W.] After the above communication of Dr. Valentin was in the printer's hands, I received, through the pohteness of Dr. Schwann, a brief notice of the results to which his observations on the DEVELOPMENT OF THE TISSUES had led him; and it affords me