Abstract: A surgical instrument for elastic ring ligation of hemorrhoids and similar body tissues by a single operator, comprising, in combination, a forceps (46) slidably disposed on ligator shaft (60) of a ligator (62) by means of a sliding fitting (58), an endoscope (20) with a track (32) fixedly attached to its inner wall, an obturator (34) receivable within the endoscope to facilitate the insertion of the endoscope into a body orifice, and a loading mandrel (78) allowing a contractible elastic ring (76) to be mounted on the ligator. The track conforms to the sliding fitting with friction sufficient to retain the forceps and ligator in place at any point along the track, but allowing the surgeon to push the sliding fitting along the track without excessive force.