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.