Abstract: Methods of and apparatus for adding toner to an electrostatographic development station from a flat-flanged container containing toner minimizes spillage of toner by automatically uncovering and recovering the container. The flat-flanged container has a mouth surrounded by a peripheral flange which is covered by a flexible cover folded upon itself and adhered to the flange. A slide cover is slidably mounted on the flange with the flexible cover attached at one end to the slide cover. The container is emptied by inserting the container into a sump lid positioned over a hopper within the electrostatographic development station and moving the container so that the mouth of the container is in alignment with an opening through the sump lid. As the container is moved into alignment with opening, the slide cover is automatically removed from the container simultaneously peeling the flexible cover from the flange and opening the container to empty the toner.