THE DARK ADAPTATION OF THE COLOR ANOMALOUS MEASURED WITH LIGHTS OF DIFFERENT HUES.

Determinations of minimum light thresholds as a function of time in the dark have been made for four color normal, three deuteranopic (or deuteranomalous), and four protanopic (or protanomalous) subjects. Measurements were made with red, reddish orange, yellow, green, violet, and white test lights. Dark adaptation curves for the deuteranopes and deuteranomalous are essentially identical with those of the color normal for all colors. The cone portions of the protanopic dark adaptation curves measured with the red, reddish orange, yellow, and white lights are higher than the corresponding data for the color normal, the discrepancy between the two sets of data decreasing from the long to short wave lengths. Dark adaptation curves for the protanopes and protanomalous measured with green and violet light are essentially normal in appearance. A theoretical explanation is advanced to account for these findings in terms of the known sensitivity characteristics of the normal and color-anomalous eye.