Iritis was produced in rabbits by the intravenous injection of either primary or purified cultures from 19 to 21 patients with acute or chronic eye diseases, and in 11 of 14 controls (laboratory assistants, healthy children, and patients with arthritis and thyrotoxicosis). Positive results were obtained with various microörganisms as follows: streptococci (alpha, beta, and gamma types), staphylococci (albus and aureus), colon bacilli, nonlactose fermenters, enterococci, and Friedländer bacilli. Iritis was produced by 44 percent of 61 purified strains of streptococci from patients with eye disease as compared with 29 percent of 69 strains from persons in the control group. Of the total of 134 cultures from patients with eye disease, 36 percent produced iritis while 17.9 percent were undetermined. Of the total of 118 cultures from persons in the control group, 29.2 percent produced iritis in rabbits, while 21.5 percent were undetermined. From the Lighthouse Eye Clinic of the New York Association for the Blind, and the Clinical Research Laboratory. Aided by grants from the Ophthalmological Foundation, Inc. Read before the Association for Research in Ophthalmology at Kansas City, Missouri, May 12, 1936. Iritis was produced in rabbits by the intravenous injection of either primary or purified cultures from 19 to 21 patients with acute or chronic eye diseases, and in 11 of 14 controls (laboratory assistants, healthy children, and patients with arthritis and thyrotoxicosis). Positive results were obtained with various microörganisms as follows: streptococci (alpha, beta, and gamma types), staphylococci (albus and aureus), colon bacilli, nonlactose fermenters, enterococci, and Friedländer bacilli. Iritis was produced by 44 percent of 61 purified strains of streptococci from patients with eye disease as compared with 29 percent of 69 strains from persons in the control group. Of the total of 134 cultures from patients with eye disease, 36 percent produced iritis while 17.9 percent were undetermined. Of the total of 118 cultures from persons in the control group, 29.2 percent produced iritis in rabbits, while 21.5 percent were undetermined. From the Lighthouse Eye Clinic of the New York Association for the Blind, and the Clinical Research Laboratory. Aided by grants from the Ophthalmological Foundation, Inc. Read before the Association for Research in Ophthalmology at Kansas City, Missouri, May 12, 1936.