After 2-3 years from the previous reports, the author reinvestigated the thyroid glands of the grown-up people and of the school children, living in the central district of Tottori
Prefecture, where several radio-active hot springs (Misasa, Sekigane and Hamamura) issue. The palpability of the thyroid gland of the grown-up people was 48.6 per cent in average ; this was significantly higher than that of the 1st report. The size of the thyroid gland of the school children has also significantly increased than
that of the 2nd report. The influence of the radio-active hot springs upon the thyroid gland was not recognized again.