Indications of the paths taken by the nerve-currents, as they traverse the caudate nerve-cells of the spinal cord and encephalon : and an abstract of a paper upon the minute anatomy of the papillae of the frog's tongue / by Lionel S. Beale.

Beale, Lionel S. (Lionel Smith), 1828-1906.

Date:: [1864]

Credit: Indications of the paths taken by the nerve-currents, as they traverse the caudate nerve-cells of the spinal cord and encephalon : and an abstract of a paper upon the minute anatomy of the papillae of the frog's tongue / 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.

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$OF THE PATHS TAKEN BY THE NERVE-CURRENTS. x\lthough the caudate uerve-vesicles, or cells existing in the spinal cord, medulla oblongata, and in many parts of the brain, have been described by the most distinguished modern anatomists, there yet remains much to be ascertained with reference to their internal structure, connexions, and mode of development. In this paper I propose to describe some points of interest in connexion with their structure. In the first place, however, I would remark that there are neither ‘ cells ’ nor ‘ vesicles ’ in the ordinary acceptation of these words, for there is no proper investing membrane, neither are there ‘ cell-content s’ as distinguished from the membrane or capsule; in fact the so-called cell consists of soft solid matter throughout. The nerve-fibres are not prolonged from the nucleus or from the outer part of the cell, but they are continuous with the very material of which the substance of the ‘ cell ’ itself is composed, and they are, chemically speaking, of the same nature. So that in these caudate cells we have but to recog- nize the so-called ‘nucleus' {germinal matter') and matter around this {formed material) which passes into the ‘fibres,’ which diverge in various directions from the cell: see Plate III. (fig. 1). At the outer part ef many of these ‘ cells,’ usually collected together in one mass, are a number of granules. These are not usually seen in the young cells, and they probably result from changes taking place in the matter of which the substance of the cell is composed. But it is not pro- y osed to discuss this question in the present paper. My special object in this communication is to direct attention to a pecu- liar appearance I have observed in these cells, which enables me to draw some very important inferences with reference to the connexions and action of these very elaborate and most important elements of the nervous mechanism. In some very thin sections of the cord and medulla oblongata of a young dog, which had been very slowly acted upon by dilute acetic acid, the ap- j)caranccs represented in Plate III. (fig. 1) were observed. Subsequently, similar appearances, though not so distinct, have been demonstrated in the$