Adaptation of the tree frog,Hyla cinerea, to colored backgrounds, and the rôle of the three chromatophore types

Measurements have been made of the spectral reflectance of the dorsal skin of living tree frogs, Hyla cinerea . The colors assumed by the frogs when placed on backgounds of different col‐ors varied with respect to both dominant wavelength (565–580 nm), purity (42–58%) and lightness (2–19%). A certain adaptation to the lightness of the background took place, whereas adaptation to hue and purity seems almost negligible. On the basis of reflection...