Multiple polyposis in recent years has been recognized as a distinct disease. This, together with the growing knowledge of the hereditary factor and high percentage of deaths from malignant degeneration, has been responsible for general interest in its study. After diagnosing a case of multiple polyposis I have undertaken to locate and examine all the members of that family group in an effort to determine how many of them were similarly afflicted. This paper represents the result. It is not, however, intended as an exhaustive review of the subject. Multiple polyposis, or adenomas, of the colon can. following the classification of Erdmann and Morris,1 well be divided into two classes: the first, the acquired or adult type, the result of some form of irritation, and the second, the adolescent (congenital, disseminated type) characterized by familial tendency and probably, in some cases at least, congenital. The acquired type is found