An apparatus which develops a latent image recorded on an image receiving member with developer material. A donor roll is positioned in a chamber of a housing having a supply of developer material therein. The donor roll transports a metered layer of developer material into contact with the latent image to develop the latent image. A rotating and translating brush gently disturbs the metered layer of developer material on the donor roll. This substantially prevent the accumulation of developer material agglomerates on the donor roll so as to create a more stable, uniform developer material layer for development of the latent image therewith.