ptc clones in the imaginal disc are capable of inducing ectopic photoreceptor differentiation and an associated outward moving morphogenetic furrow. Clones can produce furrows progressing in any direction. Within the clone randomly oriented ommatidia of both chiral forms are observed. Ommatidia born from ectopic furrows do not always rotate towards the equator but they can organise themselves around the ectopic equator. Clones induced close to the normal equator of the eye disc produce an ectopic equator that can hijack the endogenous equator leading to a single equator positioned away from the dorsoventral midline and not necessarily running precisely along the anteroposterior axis.