Here is a careful translation of Sandström's pioneering work on the parathyroid, made by a fellow countryman who is now a graduate student in medicine. The article itself is of interest to all endocrinologists, histologists and anatomists. It is a classic contribution, for the first time completely translated from the Swedish. Combined with it is a biographic note by Prof. August Hammar, which includes a letter from Sandström to his sister describing the reception of presentation of this discovery at a scientific meeting and pertinent references to earlier work on the parathyroid. The book has been carefully edited by two persons thoroughly appreciative of medical history.