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IN a previous paper (Vrabec, 1965) changes in the axons of the retinal ganglion cell in aged people were described. Similar spherical swellings of axons have also been found in voluntary muscles by Coers and Woolf (1959) and in the human optic nerve, retina, and ciliary body by Wolter (1957Wolter ( , 1963. This paper deals with other changes in the retinal ganglion cell bodies, axons, and dendrites. Material and MethodsWhole mounts of sixteen human adult retinae were studied. Retinal mounts were impregnated by the method of Gros-Schultze, which was slightly modified by shortening the time of impregnation in the 20 per cent. silver nitrate bath to 10 to 15 minutes instead of 1 to 2 hours. Human retinae from the fourth to the ninth decade were studied, ten being between 70 and 85 years. After impregnation, the whole retinae (with cross incisions in the four oblique meridians at the periphery to facilitate flattening) were mounted in Canada balsam, with the inner surface uppermost. Several retinae of other vertebrates were studied for comparison. As the retinae were mounted whole, the danger of artefacts due to breakage was avoided. It was possible, by focusing the microscope upon a particular lamina of the inner plexiform layer, to study the dendrites of large, diffuse ganglion cells spreading horizontally over wide areas, but vertically orientated dendrites could be followed only with some difficulty. High-power dry lenses with longer working distance were most useful for this work. A light compression of the mount, using a small weight during the setting of the resin, permitted the study of fine details of axons and dendrites.Anterior segments of the same eyes were cut in thick sections (60 to 100 ,u) on the freezing microtome and impregnated by the original Gros-Schultze method. FindingsIn aged retinae severe degeneration of the whole cell body occasionally occurs. Such cells are full of detritus and their dendrites are packed with argyrophilic granules (Figs 1 and 2).The other changes which are described below are, however, much more usual.

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