_Etiology_.--The functional activity of the esophagus is dependent upon reflex action. The food is propulsed in a peristaltic wave by the same mechanism as, and through an innervation (Auerbach and Meissner plexus) similar to that which controls intestinal movements. The vagus also is directly concerned with the deglutitory act, for swallowing is impossible if both vagi are cut. Anything which unduly disturbs this reflex arc may serve as an exciting cause of spasmodic stenosis. Bolting of food, superficial erosions, local esophageal disease, or a small foreign body, may produce spasmodic stenosis. Spasm secondary to disease of the stomach, liver, gall bladder, appendix, or other abdominal organ is clinically well recognized. A perpetuating cause in established cases is undoubtedly "nerve cell habit," and in many cases there is an underlying neurotic factor. Shock as an exciting cause has been well exemplified by the number of cases of phrenospasm developing in soldiers during the World War. _Cricopharyngeal spasmodic stenosis_ usually presents the subjective symptom of difficulty in starting the bolus of food downward. Once started, the food passes into the stomach unimpeded. Regurgitation, if it occurs, is immediate. The condition consists in a tonic contraction, ahead of the bolus, of the circular fibers of the inferior constrictor known as the cricopharyngeus muscle, or in a failure of this muscle to relax so as to allow the bolus to pass. In either case the disorder may be secondary to an organic lesion. Local malignant disease or foreign bodies may be the cause. Globus hystericus, "lump in the throat," and the sense of constriction and choking during emotion are due to the same spasmodic condition.