Abstract 1. Yellow and orange chromatophore pigments in the fins and tail of Mugil cephalus, Solea vulgaris and Serranus scriba were extracted with methanol and chloroform and characterized as xanthophylls. 2. The xanthophylls, which were responsible for the yellow-orange colour of the tissues, were found to be in a stable association with the particulate matter of tissue homogenates. 3. In Serranus scriba about 25 per cent of fin and tail xanthophylls disappeared after 2 days in captivity. 4. The injection of cortisol succinate did not affect the concentration of xanthophylls in Serranus.