the operating plane of the needles 13 14 within the area defined by cam 17 and the pins 16 is adapted to restrict the passage area of the fibrous material 5 in the region of the needles the stemming device 18 is attached to a base 32 and forms an arm which is shiftable by means not shown in a lateral direction between the knock off iadd over iaddend cam 17 and the counter bar 15 and pins 16 as well as vertically at a right angle to the lateral shift the face 34 of the stemming device 18 which is remote from the fibrous material 5 has a slanted portion at its upper end which terminates in point 35 at the tip of the opposite face of the stopping device a rapid compression of the fibrous material 5 induced by a predetermined constriction of the passage subsequent the operating zone of the needles causes the fibrous material to be confined in an area of substantially step shaped cross section an abutment 19 mounted on the base 32 is designed to support the pins 16 against lateral deflections which tend to arise from the push of the needle 13 piercing the fibrous material in the direction of the needle 14 according to the present invention the fibrous material 5 arrives at the operating zone of the needles 13 14 at a moderate speed induced partly by the forward motion of the conveyor belts 30 30 39 and partly by gravity acting on the weight of the material moving on an inclined surface in addition the pull of the finished textile material 2 as it is removed from the machine in the direction of the arrow x causes the strongly cohering fibrous material 5 to settle in the operating range of.