RECENTLY there has been added to the armamentarium of the surgeon a gauzelike material which is completely absorbed in the tissues and serous cavities. This material is known as oxidized cellulose. Its physical and chemical properties have already been thoroughly described in the literature. There has always been some concern expressed about leaving nonabsorbable materials in tissues and especially in the serous cavities. Nonabsorbable sutures such as silk, cotton or nylon may be left in the tissues and serous cavities with a certain degree of impunity. Gauze sponges and packs have been left in the serous cavities with untoward results such as empyema, fistula formation and intestinal obstruction. They have also been left in the serous cavities for hemostasis, and when they have been removed hemorrhage has often recurred or infection has been introduced. The use of oxidized cellulose with thrombin as a hemostatic agent has been studied by Uihlein and his