Fig. 6. Composites of micrographs from the distal ventral retina of the alevin showing the progression of retinal development from the peripheral undifferentiated growth zone (ugz), at the top of each figure, toward the (main) central retina, at the bottom of each figure. Labelling by the UV riboprobe (rtUV, A) appears closer to the ugz than labelling by the blue riboprobe (rtBL, B). Symbols and nomenclature as in Fig. 5. Magnification bar (at the bottom right of the figure) is 25 µm.