Textbook of normal histology: including an account of the development of the tissues and of the organs . cone-visual cells ; d, bipolars belonging torod cells ; e-i, bipolars belonging to cone-cells ; k-tn, horizontal nerve-cells ; «, centrifugal nerve-fibres ;o-t, ganglion-cells connected with optic fibres; a-e, spongioblasts or amacrines arranged in layers;4, d, diffuse amacrines ; rj, nervous amacrine. (Kallius after Ramon y Cajal.) inner border of the rods and the cones the expanded ends of the neu-roglia-fibres form the external limiting membrane, delicate pro-cesses extending from the la
Textbook of normal histology: including an account of the development of the tissues and of the organs . cone-visual cells ; d, bipolars belonging torod cells ; e-i, bipolars belonging to cone-cells ; k-tn, horizontal nerve-cells ; «, centrifugal nerve-fibres ;o-t, ganglion-cells connected with optic fibres; a-e, spongioblasts or amacrines arranged in layers;4, d, diffuse amacrines ; rj, nervous amacrine. (Kallius after Ramon y Cajal.) inner border of the rods and the cones the expanded ends of the neu-roglia-fibres form the external limiting membrane, delicate pro-cesses extending from the latter between the bases of the rods and thecones, which they surround and embrace as the addition to the long radial fibres, richly-branched neuroglia-cells occur within the outer reticular layer to the fibre-complex ofwhich they contribute. Within the meshes of the framework just described the ner-vous elements of the retina are distributed in a manner charac-teristic for each layer : a brief consideration of these is thereforenecessary. THE EYE AND ITS APPENDAGES. 353 Fig. 377. Ik. The nerve-fibre-layer contains the continuations of the opticfibres which, after having lost their medullary substance in theirpassage through the lamina cribrosa, radiate as naked axis-cylin-ders to all parts of the retina as far as the ora serrata. The fibre-layer is thickest at the edge of the optic disk and thinnest at theextreme retinal periphery. Sooner or later the fibres forsake theirperipherally-directed course, and, bending sharply, pass almost per-pendicularly to the ganglion-layer and other strata. The ganglion-cell-layerconsists of a single row oflarge multipolar nerve-cells (15 to 30 fi), whoseaxis-cylinder processesare directed towards the fibre-layer ; their branched pro-toplasmic processes, whenwell developed, pass into theinner reticular zone, to meetthe arborizations of the cone-bipolars. The ganglion-cells in the central part ofthe retina are densely packedin the
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Keywords: ., bookauthorpiersolgeorgeageorgea, bookcentury1800, bookdecade1890
