The nuclei tuberis laterales and the so-called ganglion opticum basale.

  • Malone, Edward F.
Date:
1914
Catalogue details

Licence: In copyright

Credit: The nuclei tuberis laterales and the so-called ganglion opticum basale. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

    14/108 (page 10)
    a shorter distance laterally, and then the tract passes over the cms cerebri, where of course it is no longer in relation to gray matter. To sum up, Series AC of man (Figs. 4 to 10) shows, in sections almost parallel to the course of the optic tract, the appearance of the three parallel columns of cells which constitute the basal optic gang- lion; one column lies in the tuber cinereum along the medio-eaudal border of the optic tract, the second extends along the dorsal (deep) surface of the tract and consists of only a few cells, while the third and largest column extends in the anterior perforated substance along the latero-oral border of the tract. The caudal column is continuous in the infundibulum with the corresponding column of the opposite side. The figures show the inevitable relation of three parallel columns in slightly oblique section. Series D of man (Figs. 11 to 18) shows essentially the same relations, but the plane of section is different. In the previous series the plane was almost parallel to the course of the optic tract, although slightly approaching the plane of a cross section; in Series D the plane of sec- tion is almost at right angles to the course of the optic tract, and both the caudo-medial and the oro-lateral borders are shown in all sections. It is evident that a plane of section at right angles to the median plane (which would cut both halves of the brain symmetrically) could not pass through the optic tract at right angles to its course, since the two tracts converge towards the median plane as they pass orally; therefore to obtain a cross section of the right tract the plane of section must lie more oral on this side than on the left. The asymmetry of the plane of section of Series D is not quite great enough to produce a cross sec- tion of the right optic tract, although this condition is very nearly attained. When Fig. 11 of Series D is compared with Fig. 4 of Series AC the location of the basal optic ganglion is rather confusing, for in the latter series it appeared caudally in the tuber cinereum near the medio- caudal border of the optic tract, while in Fig. 11 it appears first in the anterior perforated substance along the oro-lateral border; if we keep in mind the asymmetry of the section, and the fact that the cell column here shown extends further laterally than the other two columns of the cell group and that in such asymmetrical sections the lateral portion is the most oral, little difficulty should exist in realizing just why this one of the three cell columns should appear first. Fig. 12 shows practi- cally the same relations, except that the optic tract is nearer the median