are arranged side by side in the left right direction with a predetermined interval provided therebetween and each is substantially formed in a rectangular shape that is formed by penetrating the resin film the end portions of each agitator 41 in the left right direction are rotatably supported by the left and right side walls of corresponding one of the first and second toner accommodating frames 38 and 39 as shown in fig2 4 and 5 the developing frame 33 is formed continuously from a rear end portion of the toner accommodating frame 32 and includes a pair of left and right side walls 35 an upper wall 36 and a lower wall 37 the left and right side walls 35 are formed into substantially plate shapes extending rearward continuously from the respective left and right side walls of the second toner accommodating frame 39 a supply roller shaft support hole 53 is formed so as to penetrate each of the side walls 35 the supply roller shaft 26 is inserted through the supply roller shaft support hole 53 the upper wall 36 is formed into substantially a plate shape extending rearward continuously from an upper end portion of the second toner accommodating frame 39 the upper wall 36 bridges upper end portions of the side walls 35 a rear end portion of.