A spectral sensitivity curve and wavelength discrimination for the turtle Chrysemys picta picta

Abstract

A photopic spectral sensitivity curve was measured in the turtle Chrysemys picta picta by the psychopysical method of flicker photometry. The data show a maximum spectral sensitivity in the region 625–640 nm. Wavelength discrimination data obtained in the long wavelength portion of the spectrum indicates that the over-all spectral sensitivity curve represents the activity of more than a single spectral mechanism.