Fig. 37 (No. 250).--Right eye, lower half. Fig. 38 (No. 72).--Microscopic section, low power. Fig. 39 (No. 199).--Right eye, lower half.] =The Vitreous Chamber.=--In the great majority of the eyeballs under examination, it was observed that the vitreous body had become detached and shrunken, and that its remnants showed distinct signs of infiltration, and often of organisation. The appearances observed in the various cases fall naturally under a number of headings: (1) Very slight evidence of vitreous structure is discernible (Pl. II., Fig. 14). (2) Filmy masses are present in the chamber (Pl. II., Fig. 15). These either (_a_) are confined to the anterior portion of the chamber, or (_b_) take the form of a cone with its apex at the nerve head, and its base in the neighbourhood of the ora serrata and ciliary body. (3) Masses are present which give the impression of being freely infiltrated with inflammatory material, either throughout their substance (Pl. III., Fig. 16) or in isolated foci (Pl. VI., Fig. 37); these may be divided into the same subgroups, (_a_) and (_b_), as those under the previous heading. (4) A distinct fibrous organisation is noticeable in the conical masses, which represent the detached and shrunken vitreous (Pl. III., Fig. 17). (5) No detail is discernible (Pl. III., Fig. 19), owing to the fact that the retina has become detached and inextricably matted with the one-time vitreous contents, and with the iris and ciliary body. There are certain preliminary points which we must first settle: