Abstract: Substantially uniform distribution of developer in a cascade assembly for xerographic reproduction apparatus is effected as the developer slides down an inclined cascade baffle onto which the developer is dumped by a succession of buckets which elevate the developer from a sump in the cascade chamber. From the cascade baffle the developer is cascaded substantially uniformly onto a perimeter sector of the electrostatic image carrying drum of the associated apparatus. Uniform developer distribution is attained on the cascade baffle by means of an array of distribution projections.Toner dust is effectively screened from the image-free areas of the image carrying drum. This is accomplished by efficiently blocking access of the dust to the drum by the position of an effective dust baffle between the developer supply and the drum in the area where the unused developer drops into the developer sump after the developing cascade.