If there be glory in prophesying an evil event, the honor in one instance belongs to Stiles,1 who, the year following the published record of the first case of infestation with Diphyllobothrium latum native to the United States, and six years after the report of the first Canadian case, predicted that infestation with this parasite, the broad tapeworm, would become endemic in the United States. That this has come to pass can be readily demonstrated from the record here to be given and from previously published records; at least forty-one persons born and residing in the United States, and two in Canada, are definitely known to have harbored the parasite (table 1). Numerous other native cases are unrecorded, while many persons, although born in foreign countries, have surely acquired the worm in North America. In addition to this, it has been proved by Magath2 and by Essex3