A container for supplying toner to a receiving apparatus, said container comprising a base including means for connecting said container to the receiving apparatus, a containing portion having a vertical wall extending upward from said base, a cover, and guide means for guiding said cover along a curved path, the base defining an opening through which toner can move under the force of gravity, the cover being movable through said curved path from a position covering the opening to an uncovering position alongside the vertical wall, the cover being made of a material flexible enough to move through the curved path but stiff enough to be pushed back to its covering position.