Fig. 10

Sixth day phenotypes of abnormal melanophore and dull iridophore mutations (Classes VI. E and VI.F). Wild-type siblings (A,B) are compared with homozygous mutants for bry (C,D), frk (E,F) and pun (G,H). In bry mutants, iridophores are slightly dull (arrow, C), and melanophores are pale (D). Unlike bry mutants, mutants in frk and pun combine melanophore degeneration phenotypes (arrows, F and H) with very dull iridophores (E,G). The strength of the iridophore and melanophore phenotypes varies between mutations: pun has a stronger effect than frk, and indeed iridophores can only be seen in the eye (arrow, G). Note in F and H that xanthophores occupy the regions of the dorsal stripe that are without melanophores, thus implying a decrease in melanophore cell number. A,C,E and G are dorsolateral views with incident light; B,D,F and H are dorsal views of the head dorsal stripe. Scale bars, 300 μm (A,C,E,G) and 75 μm (B,D,F,H).