Light transmittance by goldfish eyes of different sizes

The transmittance of the optic media was measured in eyes from small (4.3–5.5 cm standard body length), medium (8.3–10.0 cm) and large (14.2–17.5 cm) goldfish. Few differences were observed over this size range, despite a doubling in diameter of the globe. Relative transmittance was constant (± 0.04 log unit) between 450–700 nm, and absolute transmittance through the lens was approximately constant as well. Changes did occur, however, in the shorter wavelengths: at 350 nm, transmission of large eyes was diminished by about 0.40 log unit relative to small eyes.