Teratomas of the thyroid region, either involving the thyroid gland or displacing it, have been reported sporadically since the first proved case was published by Hess in 1854. A total of 86 cases have been recorded through 1960, but in no instance has a follow-up of more than a few months been presented.7We have been fortunate in following a patient for seven years who was successfully operated upon on the first day of life, the earliest operation so far reported. I. Nature of the Tumor Morphology.—Teratomas of the neck for the most part have been found to occupy a position in the neck characteristic of the position of a normal thyroid gland; in many instances, the tumor apparently has arisen from one or other lobe of the thyroid gland itself8but more frequently has arisen separately from the thyroid gland, and in fact, in some reported