Fig. 2. Mosaic types present in the rainbow trout smolt retina. (A) Complete square
mosaic. (B) Incomplete square mosaic. (C) Complete row mosaic. (D) Incomplete
row mosaic. (E) Complete square-row mosaic. Note the large single cones
identified by the white arrowheads. (F) Incomplete square-row mosaic. For all
mosaics, arrows point to short-wavelength-sensitive (SWS) cones, while
arrowheads point to ultraviolet-sensitive (UVS) cones (complete mosaics) or
where UVS cones are missing (incomplete mosaics). Scale bars, 20 µm for all
mosaics.