In an axial flow rotary separator, each radially extending finger-like crop-engaging element of the rotor is individually and obliquely journaled on a fixed eccentric shaft. Push bars spaced 90 degrees apart rotate about the axis of the separator to drive the fingers so that the finger tips describe a circular path eccentric to the separator casing and inclined to its axis. The plane of rotation of the fingers and the speed of rotation of the rotor are chosen so that the fingers maintain the crop material in an annular mat in contact with the inside wall of the casing and propel it spirally downstream. Finger element bearing housings are split for convenient assembly and repair.