Mesenteric vascular occlusion still remains one of the most difficult surgical problems. The difficulty in arriving at an early diagnosis undoubtedly accounts for the high mortality, quoted by various writers as being about 70 per cent. The delay in diagnosis is often unavoidable owing to a lack of definite symptoms, even though the damage to the intestinal tract is severe. The same difficulty is experienced in the early clinical diagnosis of simple intestinal obstruction. The effects on the physiology of the bowel of early mesenteric thrombosis or embolism may be compared in some respects with those of simple intestinal obstruction, as well as those of the strangulation type. These conditions result in stasis of the intestinal contents, decrease in the absorption of gas and fluid by the intestinal wall, excretion of fluid into the lumen of the bowel proximal to the affected segment and intestinal hemorrhage and infarction of the