In the brains of egh³ third instar larvae, some of the axons of R-cells 1-6 fail to terminate in the lamina and project into the medulla, causing thick axon bundles in this structure. R1-R6 axons that do terminate in the lamina are disorganized and form abnormal patches in the lamina plexus.

Females with germline clones lay eggs with fused dorsal appendages and the embryos have an expanded nervous system. Only a few eggs are laid because early oogenesis is blocked due to the development of egg chambers containing multiple oocyte-nurse cell complexes. Germ cell divisions in the egg chambers are not regulated. Follicle cells at the posterior of egg chamber become mesenchymal-like indicating they have not adopted a border cell fate. Stalk cells are determined correctly but are usually disorganised compared to wild type.

Larvae grow at a normal rate until late in the third larval instar. Puparium formation can be delayed. Mosaic analysis demonstrates mutant phenotype is non-autonomous.

pharate adult lethal; growth slowing starts at various earlier stages; survive in hemizygous condition in gynandromorphs; hemizygous eyes rough. Pharate adults dissected from pupae show rough eyes, sparse microchaetae, and incomplete dorsal midline; XY but not X0 males of both rescued by Dp(1;4)w^m65g, exhibiting phenotype of dissected pharate adults described.