Several years have elapsed since Dr. R. Berlin described a series of cases in which he had observed a peculiar retinal change after the eye had been struck with a blunt object, as, for example, a stick or a stone. Under those circumstances he noticed a cloudiness of portions of the retina, not involving the retinal blood vessels. The milky appearance reached its height in twenty-four to thirty-six hours, and disappeared in two or three days. Berlin pointed out that the rapidity with which the cloudiness developed, and the length of time that it persisted, stood in direct relationship with the severity of the original injury. This curious condition, which Berlin called _commotio retinæ_, was associated with some reduction of sight, episcleral congestion, and a difficulty in getting the pupil to dilate when atropine was dropped into the eye. Small retinal hemorrhages were sometimes present. Berlin explained the ophthalmoscopic picture by supposing that a rupture of the choroid was followed by bleeding and œdema of the retina. This theory has recently been opposed by Denig. That observer, as the result of experiments upon rabbits, believes that the blow upon the eyeball causes the vitreous to impinge upon the retina, to tear the internal limiting membrane, and to force the vitreous into the nerve-fiber layer. The alternate elevations and depressions thus brought about in the nerve-fiber layer of the retina are, according to Denig, the cause of the ophthalmoscopic appearances. Since the publication of Berlin’s original paper few cases of _commotio retinæ_ have been recorded. Indeed, the retinal changes are of so fleeting a nature that an opportunity for observing them must occur comparatively seldom. This fact leads me to place upon record brief notes of a somewhat interesting case: E. S., aged eleven years. First seen on July 25, 1899. _History._—At 6.45 P. M., on July 24, the patient was struck in the right eye with a cricket ball, made of cork and covered with rag cloth.