The Relation of the Eyes to Chromatophoral Activities

Abstract

Eyeless specimens of Rana pipiens, Palaemonetes vulgaris, Fundulus heteroclitus, and Amciunis nebulosus quickly attain a dark coloration and in the light retain this tint irrespective of the environment. This dark condition is true of the majority of other eyeless amphibians, crustaceans, and fishes under like conditions. In darkness eyeless Rana and Palaemo-netes are of the same tint as in the light, but Fundulus and Amciurus assume a lighter shade, showing that there must be some other element than the eye that influences their chromatophores. The concentration of pigment in chromatophores is believed to be due to one factor, a concentrating neurohumor; its dispersion to 2, a dispersion neurohumor and the innate action of the chro-matophore itself. Chromatophores, unlike striped muscle, exhibit no state that may be rightly called a state of Test, as opposed to one of activity.