The Effects of Hypophysectomy and Anterior Lobe Administration on the Skin and Thyroid of Triton Cristatus

THE skins of many vertebrates react to variations in the amount of hormones of the endocrine glands, especially of the thyroid and pituitary. Moulting in Triturus viridescens is inhibited after both thyroidectomy and hypophysectomy or both operations simultaneously performed. The cornified layers continue to form and the accumulation of these makes the animal appear grimy (Adams and Richards, 1929; Adams, Richards and Kuder, 1930; Adams, Kuder and Richards, 1932). The series of experiments here reported demonstrates that a similar effect occurs after hypophysectomy in immature or mature Triton cristatus (Adams, 1931a). The moult in Triturus viridescens operated in the above ways can be induced by various methods. Supplying thyroid hormone by thyroid grafts or thyroxin injections, or administering iodine to thyroidectomised or hypophysectomised animals or to ones lacking both glands, or stimulating the thyroid glands of hypophysectomised animals either by giving pars anterior grafts or injections or by pinching them in situ, will cause the shedding of the cornified layers (Adams et al, 1930, 1932; Adams, 19316, 1932). Similarly in hypophysectomised Triton cristatus, the moult can be induced by administration of pars anterior substance or by injection of certain extracts of mammalian anterior lobe.