Of the innumerable organs and tissues which have been made the subject of research since Brown-Séquard promulgated his doctrine of “internal secretions,” it may be broadly stated that there are practically two only in which the existence of such a specific secretion has been determined beyond controversy, viz., the thyroid gland and the suprarenal bodies. The place of the former in therapeutics is now more or less determined; at all events most have tried it and formed their own conclusions; but the uses of the suprarenal glands in treatment are still, to a large extent, undecided. It is true that in certain branches of surgical practice suprarenal extract has been found so useful as a local application that it may almost be said to have gained a position in the surgeon's regular armamentarium, and that it has been employed internally in Addison's disease by many observers, with somewhat conflicting results (1); while its use in cases of heart failure, and also in obstetrics, has recently been strongly urged (2). But beyond these more obvious applications of the properties of its active principle, there are certain other diseases, notably some forms of psychoses, in which it would seem probable that those properties might render it valuable, and what little use has been made of it in this direction to some extent bears out this expectation.