THE PURPOSE of this paper is to present, as accurately as possible, an analysis of the cases of lingual thyroid reported to date, including all available historical data as to embryology, incidence, anatomicopathologic features, diagnostic procedures, and treatment. There is also added a personal case, with clinical history, operative procedure employed, postoperative course, and a clinical and basal metabolism check over a 12-month period. Sketches of the tumor mass and the operative technique are included, as are photomicrographs of sections of the tumor. HISTORICAL DATA The first case is credited by all writers to Hickman,1 an Englishman, who reported, in 1869, the death by suffocation of a newborn baby with an enormous thyroid tumor in the base of the tongue. A close study of the description by Hunt,2 an American, in 1865, of his experience with a case of tumor on the base of the tongue in a