Fig. 6. Genetic interactions between gp150 and Delta. Tangential sections of adult eyes are presented. (A) The gp150^P8/gp150² eye exhibits ∼19% (n = 578) mutant ommatidia. (B) Reduction of Dl function strongly enhances the gp150 mutant phenotypes. Up to 68% (n = 544) abnormal ommatidia, which contain more R cells (arrow), fewer R cells (arrowhead) or apparently fused ommatidial units, were found in gp150^P8/gp150²; Dl^9P/+ flies. Often rhabdomeres exhibit abnormal morphology (circled asterisk). (C) gp150²/+. The arrow points to an occasionally observed aberrant ommatidium. (D) Dl^9P/+ flies, no mutant ommatidia can be found. (E) gp150²/+; Dl^9P/+. The circle indicates a fused ommatidium and the arrowhead points to an ommatidium missing an outer R cell.