Quain's elements of anatomy . ganglion ; d, principal group of nerve-cells, with fibres passing down from amongst the cells, probably to unite with thelongitudinally coursing nerve-fibres by T-shaped junctions (see text). (fig. 153). The nervous cords on entering lay aside the perineuralsheaths, which become merged into the general connective tissue of theorgan ; and spread out into smaller bundles, between which the 156 NEEVOUS SYSTEM. gangiion-cells are interposed ; and the fibres are gathered up again intocords, furnished with perineural sheaths, on issuing from the ganghon. Fig. 154. Fig.
Quain's elements of anatomy . ganglion ; d, principal group of nerve-cells, with fibres passing down from amongst the cells, probably to unite with thelongitudinally coursing nerve-fibres by T-shaped junctions (see text). (fig. 153). The nervous cords on entering lay aside the perineuralsheaths, which become merged into the general connective tissue of theorgan ; and spread out into smaller bundles, between which the 156 NEEVOUS SYSTEM. gangiion-cells are interposed ; and the fibres are gathered up again intocords, furnished with perineural sheaths, on issuing from the ganghon. Fig. 154. Fig. 154. -A BIPOLAR NERVE-CELL, WITH ITS POLES PROLONGED INTO MEDULLATED NERVE-FIBRES (Key aud Eetzius). The wliole is invested by the primitive B, B, nodes of Tlie nerve-cells have mostly a round, oval, or pyriformfigure. Each cell is inclosed in a transparent capsule withnuclei upon its inner surface, (figs. 155,156) ; these capsulesare continuous with the primitive sheaths of the nerves (). Fig. Fig. 155.—A GANGLION-CELL WITHIN ITS SHEATH ; FR05I THE HUMAN SYMPATHETIC. HiGHLT MAGNIFIED. (Key and Rctziiis.) Of the relation between the nerve-fibres in a ganglion andthe ganglion-cells, it is probable that some fibres may passthrough without being connected with the cells, but thatevery nerve-cell is connected with a fibre or with fibres. Inthe case of niulti-polar cells (fig. 155), such as are found inthe sympathetic ganglia, each of the branches of the cell is inall probabihty continuous with a nerve-fibre, and the sameis certainly the case with bipolar cells, at least those in whichthe two poles are prolonged from oi^posite extremities of thecell as in the spinal ganglia of fish (fig. 154), as well as GAl^GLIA. 157 in the pyriform cells before noticed (see p. 148, and fig. 146) in whichtwo processes arise from a part of the cell near one another, and arecontinned in opposite directions, either at once, or after the one fibrehas made two or more s
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