(b) Yet the fibres that Schewiakoff observed and associated with special visual cells occur beyond question. Fig. 64 is a drawing of the first cut through the vitreous body of Charybdea, and in among the sections of the pigment streaks are seen sections of processes lying within clear spaces exactly as Schewiakoff figures his visual fibres (’89, Taf. II, Fig. 18). That the fibres occur is indisputable, but as to the cells to which they belong I can say nothing except that from such evidence as I have given in the preceding paragraph I conclude that they come from pigmented retinal cells of not very different type within the retina from the others, if different at all. (c) On the third point, that the pigment streaks in the vitreous body belong to underlying cells and are continued distally into fibrous processes like the visual fibres of Schewiakoff, the evidence is decisive. Fig. 58 has already shown it, and if this were not enough, a case of unusual stoutness of the fibres drawn in Fig. 67 is conclusive. The preparation from which the section is taken was one preserved with corrosive-acetic, and I have drawn the outlines with the camera in order to avoid exaggeration of the fibres as far as possible, and also to show the shrinkage of the vitreous body (_vb_). It is the shrinkage of the vitreous body that makes it so difficult to determine the exact relation of structures seen in the vitreous body to the retina. The fibrous processes run through the vitreous body to the “capsule” of the lens (_cp_) (see also Fig. 72), a layer of homogeneous substance much resembling that of the vitreous body, which is classed as a part of the vitreous body, but usually in the shrinking adheres to the lens. The capsule is therefore regarded by Schewiakoff as a secretion of the lens cells. Some fibres were found by him to have the appearance of branching upon reaching the surface of the capsule, others of passing through it and of seemingly ending among the cells of the lens. The same appearances were given in my sections. It is altogether impossible in the distal portion of the vitreous body to distinguish between the fibres of Schewiakoff and those that come from the long pigment cells. (Figs. 64-66 represent the appearance of the vitreous body at successive levels, and are from the same series of sections as Figs. 59-62 and 72.) In Fig. 64 the sections of the processes that Schewiakoff calls visual are easily distinguished from the sections of the long pigment cells. In Fig. 65, which is two or three sections nearer the lens, the pigment cells are shown by their cross-sections to be tapering down, and in Fig. 66, nearer still to the lens, the two kinds of processes are no longer to be distinguished from each other. In a few cases I have found pigment in a fibre which but for this would be called one of the visual fibres of Schewiakoff. Such considerations as these, the similar appearance in