Fig. 4. FGF signaling is essential for rescue of ichabod by Squint but not by Bozozok. XFD completely blocks rescue by Sqt (A-D) but not Boz (E-H). Typical examples are shown of uninjected ichabod embryos (A,E), and ichabod embryos injected with RNAs for sqt (B), boz (F), sqt and XFD (C), boz and XFD (G), sqt and d50 (D) or boz and d50 (H). Many embryos injected with boz and XFD RNAs form eyes (arrow, G). (I,J) Phenotypic classification of the embryos shown in A-D(I) or E-H (J). The asterisk indicates embryos similar to those shown in G and the double asterisk class is highly dorsalized. Embryos are shown at 24 hpf.