Exophthalmic goiter is a disease whose etiology is far from a settled question. Many studies have been made by workers on large groups of patients. Their conclusions differ so widely and also differ so much from personal experience that it must be concluded that the disease has a varied etiology. All students of this disease agree that the nervous system in its entirety plays an important rôle. It is well known that emotional stress and psychic upsets often seemingly initiate this disease. Careful study is necessary, however, to prove this statement. It is probably true that many cases are such mild types of the disease that they have been overlooked. Any severe or unaccustomed shock to the emotional make-up of the patient may aggravate the symptoms and change a mild case into a severe one. Latent cases, or those which are constitutionally or potentially cases of exophthalmic goiter, may really