New observations upon the structure and formation of certain nervous centres : tending to prove that the cells and fibres of every nervous apparatus form an uninterrupted circuit / by Lionel S. Beale.

  • Beale, Lionel S. (Lionel Smith), 1828-1906.
Date:
1864
Catalogue details

Licence: Public Domain Mark

Credit: New observations upon the structure and formation of certain nervous centres : tending to prove that the cells and fibres of every nervous apparatus form an uninterrupted circuit / by Lionel S. Beale. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    16/52 (page 10)
    4. Of the spiral fibres of the fully formed ganglion-cell, and of the ganglion-cells of different ages. In all but very young ganglion-cells the remarkable spiral fibres already alluded to exist. In fig. 1, which represents a fully formed cell, the beautiful spiral arrangement of one of the fibres is observed, and in figs. 21, 22, 27, & 28 several fibres are seen to proceed from one ganglion-cell. Close to the cell in which there is a considerable extent of spiral, the course of the fibres is almost transverse. The fibres seem to be coiled around the lower thinner portion of the ganglion-cell (figs. 1, 3, 4, 20, 25, 31). Then the fibres pass spirally round the straight fibre away from the cell, and each turn becomes more oblique than the one above it, until at last the fibre (or fibres) lies parallel with the other fibre which leaves the cell. The spiral fibres are necessarily longer than the straight fibre. The spiral fibre eventually takes a course in the compound nerve- trunk to which the fibres may be traced, the very opposite of that taken by the straight fibre; so that, although the two fibres run parallel to each other for some distance from the ganglion-cell, as Stannius observed was the case in the bipolar cells of the calf, it is certain that, at least in many instances, they at length pass in opposite directions (fig. 1). Kolliker thinks that “ by far the greater part, perhaps all,” of the fibres from the ganglion-cells of the spinal nerves pass in a “ peripheral directionbut I believe this statement is erroneous, both as regards the existence of but one fibre, and its course. I have never been able to find any ganglion, large or small, the fibres of which passed in but one direction. Even when a ganglion consists of only three or four cells, compound fibres pass from it in different directions. I doubt if a nerve-cell anywhere exists whose fibres pass to their destination in the same direction. In connexion with this question I may revert to the fact I have already stated *, that whenever any compound nerve- trunk, large or small, composed of any form or number of nerve-fibres in any part of the organism of man or animals, passes into another trunk running at, or nearly at, right angles to it, its component fibres divide into branches which pass in opposite direc- tions. This general fact is most important; and I have never seen anything to make me believe that the disposition is not universal, and therefore essential even to the simplest nervous apparatus. As the disposition exists in bundles of fibres which there is reason to believe are purely sensitive, as well as in the case of those which are purely motor, it looks as if fibres invariably passed in two directions, whether they be traced from their peripheral distribution or from their central origin. The arrangement spoken of is represented in fig. 40, which is from the submucous areolar tissue of the palate of the frog f. The spiral fibres can be shown to be continuous with the material of which the body of the cell is composed as well as the straight fibre; but the former are connected with its surface, while the latter proceeds from the more central part; so that, in the most * Philosophical Transactions for 1862, page 894. t See a paper in my ‘Archives,’ “ On the Branching of Nerve-trunks, and of the subdivision of the individual fibres composing them,” vol. iv. p. 127.