In the previous and familiar {Z.r,Z.i} plane each Z trajectory can wander over the entire image plane. When we project onto a major plane involving one of the C axies, each point in each Z trajectory will appear to wander only along a single image row or column as determined by the particular random initial C. This is most easily imagined by thinking of the above image as being a "side-to-side view" through a 3D box who's front-to-back view gave the previous image. Of course the box is really four dimensional but the analogy is accurate.