Response of Isolated White Chromatophores of Crustacea to Change of Illumination

Abstract

IT is now generally accepted that the movements of pigment in the light-absorbing chromatophores of decapod Crustacea are controlled by the secretion or secretions of some tissue in the eye-stalks. In addition, many species possess chromatophores which contain a white light-reflecting pigment, the movements of which continue after the eyes and eye-stalks have been amputated. Therefore, it has been suggested that some tissue in the rostral region may affect these white chromatophores, by a secretion which is released in darkness under the control of some exteroceptor other than the eyes^1,2. However, the results of injection experiments have indicated³ that the diurnal movements of the white pigment are not under hormonal control, but that the white chromatophores behave as ‘independent effectors’⁴.