In the developing apparatus for producing an electrostatic latent image on a charge retaining member such as a drum, a rotating member for producing a shifting magnetic field is used to transport magnetic toner from a toner source to a developing area on the drum. The amount of toner so transported is regulated by the present invention by a magnetizable member positioned adjacent the rotating member in front of the developing area, the magnetizable member being characterized by a curved surface on which a shifting magnetic field is induced by the said rotating member and which attracts excess toner from the latter.
