Diseases of the nervous system / edited by Archibald Church.

Date:
1908
Catalogue details

Licence: In copyright

Credit: Diseases of the nervous system / edited by Archibald Church. Source: Wellcome Collection.

    71/1256 (page 43)
    31, b, and 32, b) and from the vascular sheaths of the arachnoid (Fig. 32, c) which form septa between the convolutions and folds (Fig. 31, a, Fig. 32, b, and Fig. 32, g) are formed of connective tissue; these are carried from the larger vascular trunks a certain distance within the gray substance. The vessels themselves with their walls, and even the capillaries, form a trabecular structure which is not without im- portance. The chief support is given by a specific sub- stance, the glia tissue. This has a characteristic structure and a peculiar tinctorial property. Wei- gert, and subsequently other authors (especially Benda), succeeded in iso- lating the glia tissue from other tissues, espe- _ m . , Fig. 32.—Transverse Section through the Upper Lumbar cully the connective, and CoED_ (After ToIdt0 staining it. Like the nerve substance originating from the ectoderm (according to His, neuroblasts’ and spongioblasts), the neuroglia presents embryologically a compact net of trabeculae which vary greatly in their caliber as well as in their density and arrangement. A thickly woven network of trabeculae surrounds the brain and spinal cord, another covers the walls of the ventricles and the central canal of the spinal cord. It forms a network (Fig. 33) in the gray substance that surrounds the nerve- cells and their processes. The glia of the white sub- stance is less dense; it passes between the nerve tubules in a loose fold, en- closes isol ated bundles (Fig. 34) of these, and to some extent penetrates into the anterior and posterior nerve roots. Many of the nuclei which are sometimes sur- rounded by a layer of pro- toplasm are deposited in the midst of the glia net, preferably in the white substance, where several glia trabeculae cross each other. It is still a mooted question whether these fibers unite with the glia cells (glia nuclei, Deiter’s cells, spindle cells) (Fig. 36), Fig. 33. — Transverse Section through the Normal Gray Substance of the Anterior Horn of the Spi- nal Cord.