THE RÔLE OF THE HYPOPHYSEAL MELANOPHORE HORMONE IN THE CHROMATIC PHYSIOLOGY OF FUNDULUS

Abstract

After hypo-physectomy in Fundulus, denervated melanophores cannot exhibit the normal black-background response. Normally innervated melanophores are only slightly affected. The inability of the denervated melanophores in hypophysec-tomized animals to expand completely is due to the absence of the hypophyseal melanophore hormone from the blood. There is sufficient melanophore hormone in the pituitary and in the circulating blood of Fundulus to establish it as a significant agency in the melanophore responses of this teleost.