toward the taker in roller 20 and a cylinder under casing 23 arranged on the lap delivery side of the taker in roller 20 and below a conventional cylinder not shown a taker in under casing c is disposed below roller 20 and between the cylinder under casing 23 and the dish plate 25 so that undesirable matters such as impurities and short fibers are separated from the lap at the taker in under casing due to the action of a stream of air generated by rotation of the taker in roller 20 in order to adjust the quantity and quality of what is to be removed at the taker in under casing c it is required to change the position of the taker in under casing c that is to vary one or both of the spacing l between the downstream end or nose of the dish plate 25 with respect to movement of the lap and the upstream end of the taker in under casing c with respect to movement of the lap and the gauge h between the cylindrical surface of the taker in roller 20 and the downstream end or tail of the taker in under casing c in fig1 to 3.