201 and through pipe 160 of lower member 159 of the superposed layers of the paper bag the portions close to the pinched edges are first opened apart upward and downward by the suction through the large suction ports following this the pinched portions of the bag which are simply pinched by elastic means are caused to slip off by the suction through the rest of suction ports and in an instant the opening of the paper bag is fully opened to the inner recessed contours of the upper and lower bag opening members the bag is now fully open up to about 15 cm from the open end and is thence gradually closed toward the opposite end which is sealed most of the bag remaining flatly closed after the opening of the paper bag a hollow guide cylinder is inserted into the open portion of the bag to prepare for the introduction of a lot of end closures from the trough g 34 into the bag the guide cylinder part k for this purpose comprises as shown in fig1 a hollow guide cylinder 451 a stationary arm 452 hanging down from the rear of guide cylinder 451 a drive arm 453 for moving the guide cylinder back and forth in parallel with the direction of travel of the end closures and support rails not shown for supporting the guide cylinder during its reciprocating movement the guide cylinder has an outside diameter slightly smaller than the diameter of the rounded opening of the bag to facilitate the insertion into the bag the guide cylinder wall is tapered at the front.