ORGANISMS having the morphologic characteristics of Toxoplasma, some appearing in pseudocysts, have been identified in chorioretinal lesions in 41 eyes removed from patients between the ages of 16 and 72 years. Twenty-seven of these patients were males and 14 were females; 40 were white, and 1 was a Negro. The lesions were unilateral, although in one instance scars of old choroiditis had been observed clinically in the opposite eye. In one patient chorioretinitis followed childbirth. One patient had mild diabetes; one, rheumatoid arthritis; one, a history of severe tonsil and tooth infection, and another, a history of gall bladder attacks and heart decompensation. One patient had a sore throat when chorioretinitis was first noted. An inguinal-node lesion which was histologically similar to that in the eye was found in another patient. As far as could be determined, 34 patients were free from symptoms of disease apart from the eye; however,