The chamber angle of the higher monkeys is structurally closely similar to that of man and differs considerably from that of lower monkeys and other mammals (Rohen1,2). It is therefore of special interest to study glaucoma in higher monkeys. We have only been able to find one case of glaucoma in the monkey mentioned in the literature, and this eye was not investigated either physiologically or morphologically (Smythe3). During work on the eye of the East African vervet (Cercopithecus aethiops) we incidentally observed two cases of secondary glaucoma and one case of what might be simple glaucoma among 111 vervets. These cases form the material of the present report. Material and Methods The vervets had been collected on the Sese Island in Lake Victoria by professional trappers and were used within a few weeks after capture. All the monkeys were used under general anesthesia. As a rule, topical