Straub[2] has described some experiments which he made on animals, in the course of which he injected pathogenic organisms either into the vitreous or into the ciliary body. The result varied according to the part infected, and the poisoned area attracted leucocytes by chemotaxis to itself. Particular interest attaches to the following of his findings: (1) The optic nerve head was swollen and filled up with leucocytes; (2) there was evidence “that the lymph current of the vitreous goes by the optic nerve, and that chemotaxic substances are brought by this current from the granuloma (the artificial infection) to the nerve”; (3) the leucocytes found in the vitreous showed the way from the granuloma to the cup of the optic nerve--they were seated on thin membranes, and most of them were heaped together in small dots; (4) aggregations were found on the walls of the cavities of the eye (on the cornea, on the retina, on the lens capsule, etc.), attracted there, in Straub’s opinion, by a chemotaxic action. [2] “The Pathology of Dust-like Bodies in the Vitreous,” etc., Trans. of the O.S. of the U.K., 1912, xxxii. 60. In the experiments above considered, which were very limited in number, an effort was made to localise the infection to one or other part of the eye, and to work with a virus (tubercle bacilli) which was comparatively constant in its toxicity. What Straub did with a few eyes has been done in the series now before us, by the Indian coucher, in fifty-four. The interest of the experiments is heightened by the fact that, whereas in the Dutch experiments the toxicity of the virus was kept as constant as possible, in the Indian ones it varied from that of organisms which took many years to destroy the sight to that of one which at once produced a fulminating panophthalmitis. One point more: The Indian operator made no effort to confine his procedure (and with that procedure went infection) to any one structure; sometimes he attacked the lens from in front, and in doing so he often primarily injured the iris, but may have spared the vitreous chamber; sometimes he entered through the ciliary body or through the choroid, opening up the hyaloid cavity in doing so. His want of skill and the slenderness of his anatomical knowledge made him catholic in the damage he inflicted, but running through his work is the trail of septic infection of the eyeball by penetrating wounds. The result is that he has provided us with a large material of extraordinary interest in the study of the problem which Straub started on. _The Filmy Masses in the Vitreous Chamber._--As has already been stated, the contents of the vitreous chamber in these specimens vary from thin gauzy films, which can only be detected by careful search, up to thick masses which strike the eye as soon as the specimen is looked at.