The salamaiiclei-tliyi*oid gland has been studied extensively, especially from the standpoint of tlie role of this gland in development and Inetamorplrosis. Studies on adult animals are chiefly confined to thc effects of thyroid removal. Hpperthyroidism in the adult salainan~lor has received little attention. Likewise the problem of the cliangcs in metabolisni associated with the athyi-oid aiid Iiypci*thyroid states in mature aniphibiaiis has not been investigated to any extent. Work of this nature has, of course, been done by many investigators working with higher types of animals.It would seem that data of this kind for the salamander would be of special value since the reaction of these animals to disturbaiice of thyroid function is niost serere. On tlie basis of expcriciicc gained in this laboratory with many hundreds of tliyl.oiclectornize(~ salainaiitlci+s covering a period of 5 years, it appears t lint tliyroidless Triturus torosus will die in less than a year when kept at room temperature. A4dams and associates ('32) reported similarly for Triturus viridescens. They found that the longest periods of survival after thyroid removal were 182, 183, 204, 229 and 286 days. Mammals, including man, are not nearly so adversely affected.