Manual of human histology . of theinner layer are a trifle larger than those of the outer, andwhen they are oval, as is most usually the case, I find thatthey are placed with the long axis in the direction of thethickness of the retina, so that theirprocesses, like those of the externallayer, run directly outwards andinwards. 3. The layer of cineritious cere-bral substance (fig, 302 e) is prettysharply defined on the side of thegranular layer, and less so towardsthat of the fibres of the optic nerve,between the elements of which itpenetrates more or less. It is com-posed of a finely granular «
Manual of human histology . of theinner layer are a trifle larger than those of the outer, andwhen they are oval, as is most usually the case, I find thatthey are placed with the long axis in the direction of thethickness of the retina, so that theirprocesses, like those of the externallayer, run directly outwards andinwards. 3. The layer of cineritious cere-bral substance (fig, 302 e) is prettysharply defined on the side of thegranular layer, and less so towardsthat of the fibres of the optic nerve,between the elements of which itpenetrates more or less. It is com-posed of a finely granular «2a^r«>, cor-responding exactly with that of thegrey substance on the surface of thecerebrum and cerebellum, and of nu-merous nerve-cells scattered in the latter, some, particularly in the outer half of this layer,which is 0-008—0-012—0-02 thick, are small (0-003—0006), inconspicuous, and in fresh preparations recognisable Fig. 305, Neive-cells with processes from the 7etina of the Ox, x 350 diam. Fig. 374 SPECIAL HISTOLOGY. only by their beautiful vesicular nuclei; whilst another por-tioUj forming an almost continuous layer on the inner side,are of larger size (0-006—0-016), These cells are usuallypyriform or roundedj or occasionally prolonged into 3—5 angles ;and most of them, perhaps all, are furnished with pale pro-cesses like those of the central nerve-cells—which were firstnoticed by Bowman ( Lectures/ &c., pp. 84 and 125), andafterwards also described by Hassail, Corti, and myself.^The processes occur either single or in numbers varyingfrom two to six and more; are at first as much as 0002wide, but in their further course continually diminish in size,under repeated divisions, till they are reduced to fine filamentsof scarcely 00004 in diameter, which, in isolated- cells, termi-nate in torn ends. In every case in which I have noticedthese nerve-cells distinctly in situ, their processes were givenoff towards the exterior, and afterwards in their
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Keywords: ., bookcentury1800, bookdecade1850, booksubjecthistolo, bookyear1853
