Fig. 4. Lack of Bgb eye phenotype in a lz⁺ background. (A) Somatic clone of Bgb^D/Bgb^D tissue in the eye. The mutant tissue was first identified at low magnification using the difference in pigmentation between the mutant and the wild-type tissue. This boundary was subsequently marked in the SEM with the black dotted line. No defects are evident in the external structure of the facets within the clone. (B,C) Plastic section through a somatic clone of Bgb^D/Bgb^D tissue. (B) In this clone, marked by the lack of pigment granules, the R1-6 and R7 cells (1-7) appear completely normal. (C) In this deeper section of the same clone, R8 cells (8) are seen to develop normally.