The epigastric distress due to extragastric lesions may so closely resemble that due to peptic ulcer that a detailed study is necessary for the differentiation. The present study is concerned with the mechanism of the epigastric distress associated with a spastic colon and chronic appendicitis. The fundamental factors responsible for the epigastric distress in these conditions are no doubt common to conditions caused by other extragastric lesions. Clinical observations1 indicate that the discomfort is induced by a stimulation of the stomach. In a former investigation2 a reflex stimulation of the stomach from the colon, appendix and gallbladder was demonstrated in the dog. The introduction of a few drops of croton oil in the proximal colon was usually followed by an increase in tone and a striking increase in the peristaltic action, particularly of the pyloric portion of the stomach. When the irritation was confined to the appendix or applied to