Abstract: In a collecting bag comprising a bag member formed by two film blanks with joined edges and an inlet opening for connection of the bag to a body orifice provided in one of said film blanks, an elongated discharge portion ending in a discharge opening is connected with the bag member, said discharge portion having a width permitting opening and reclosing by manual unfolding and folding operations and defining a narrowed discharge passage for the discharge of more or less entirely liquid body wastes, a substantially free flow through the narrowed discharge passage in the open unfolded condition of the discharge portion and thereby a free discharge flow of the bag content being obtainable by arrangement of a flexible hose member in the discharge passage.