Much has been written concerning the changes in the temperature of the extremities due to sympathetic vasoconstrictor activity. Few references are found in the literature regarding variations in the temperature of the nasal mucous membrane. For several years, during the routine preoperative examination of patients before operations on the thyroid, I have noted that the mucous membrane of the nose in patients with high basal metabolic rates has been thin. Edema, except in the presence of an acute upper respiratory infection, has been rare. On the other hand, in patients with metabolic rates below normal, the mucosa has frequently been boggy and edematous, much the same as the nasal membrane of an allergic patient. This clinical observation suggested investigation of possible temperature changes in the nasal membrane similar to the changes in the extremities in Raynaud's and Buerger's disease. For this work I have used the same type