Abstract: A conveyor having a tubular endless belt with lateral beads to be engaged by drive and idler pulleys and with clip springs to load the longitudinal edges of the belt into abutting relationship. In order to supply and discharge material respectively to and from the hollow space of the conveyor at desired locations along the conveyor path stationary pressure rollers separate the longitudinal edges of the belt against the bias of the clip springs. Alternatively, power can be used to separate the longitudinal edges of the belt, the power having pulleys engageable with the beads of the belt. To facilitate the discharge of material from the conveyor guide rollers provide a convex bight in the belt along the inner run thereof immediately ahead of the discharge location.