Quain's elements of anatomy . the line of Vicq dAzyr is very distinct but the inner line of Baillargeris not visible (fig. 308, 2). This grey substance of the convolutions contains cells and fibres STEUCTFEE OF THE GREY MATTER. 357 embedded in neuroglia,with numerons blood-vessels, which pass verticallyinwards at the surface but in the deeper ]Darts are more irregularlydisposed. The cells are of various forms and sizes, many of them with numerousprocesses. Some of these branching- cells are irregular in form and posi-tion, but the majority are more regularly pyramidal in shape, with theapex of
Quain's elements of anatomy . the line of Vicq dAzyr is very distinct but the inner line of Baillargeris not visible (fig. 308, 2). This grey substance of the convolutions contains cells and fibres STEUCTFEE OF THE GREY MATTER. 357 embedded in neuroglia,with numerons blood-vessels, which pass verticallyinwards at the surface but in the deeper ]Darts are more irregularlydisposed. The cells are of various forms and sizes, many of them with numerousprocesses. Some of these branching- cells are irregular in form and posi-tion, but the majority are more regularly pyramidal in shape, with theapex of the pyramid tmned towards the surface of the convolution. Theaverage size of the larger pyramidal cells is tsVo^^ of an inch in dia-meter at the base, and each has a rounded nucleus having an averagediameter of „g^ooth of an inch. They generally contain a little yellowishpigment. The cells often appear to lie m distinct cavities in the greymatter (pericellular spaces), but it is uncertain if these are natural or Fig. Fig. 308.—Sections of cerebral con-volutions (after Baillarger). The parts are nearly of the natural , shows the six lajers ordinarily seenin the cerebral cortex when carefullyexamined with the naked eye ; 2, theappearance of a section of a convolutionfrom the neighboui-hood of the calcarinefissure. produced by shrinking after death. The process from the apex of eachcell may be traced for some distance towards the surface of the con-volution giving off one or two branches as it passes outwards. Themode of termination of these _ branches is unknown. Several finebranching processes pass from the angles at the base of the cell andrun outwards or towards the medullary centre. Some of these pro-cesses divide and ramify, the branches forming a network of fine anasto-mosing fibres, while others have been traced inwards undivided, andone process at least from each cell is probably continuous with the axis-cylinder of a nerve-fibre. The undivided axis-cylin
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Keywords: ., boo, bookcentury1800, booksubjectanatomy, booksubjecthumananatomy
