Cystoid degeneration of the retina, studied in 1,000 eyes from 500 autopsy cases was present in all specimens from persons eight or more years of age. It involved the sexes equally, showing a linear increase in severity with age until the seventh decade. The extent of involvement in each sector of peripheral retina correlated closely with the total for a given eye, and the distribution pattern was very similar in both eyes of a given case. Retinal involvement was greater superiorly than inferiorly, and the temporal and nasal horizontal meridians were relatively spared. Cystoid degeneration was unrelated to eye size, to gross features of the virtreous body, and to chorioretinal lesions; the relationship to senile retinoschisis was not clear. Only eight of 71 peripheral retinal holes occurred in areas of cystoid involvement. Cystoid degeneration appears to be even more innocuous than is generally believed.