Mosaic analysis of neurA,B show phase-contrast micrographs of sections through eyes containing neur homozygous cells. The mutant cells lack pigment granules, which in photoreceptor cells are normally seen as dark bodies at the base of the rhabdomere. Photoreceptor cells are identified by number (R1, R2 etc) from salient ommatidia. Green numbers reflect morphologically normal, neur/+ or +/+ photoreceptors. Magenta indicates morphologically unaffected, neur mutant photoreceptors. Blue indicates morphologically transformed, neur/+ or +/+ photoreceptors. Panel A shoes several examples of neur mutant R3 cells that develop normally but are associated with R3>R4 transfromation by adjacent, neur/+ or +/+ cells. Panel B shows an ommatidium with neur mutant R1 and R6 cells. Although these cells appear unaffected, the neur/+ or +/+ cell in the R7 position adopted R1/6-like morphology.