As the study of mental diseases has become compulsory on all medical students, good text-books, arranged in a manner which leads to an easy understanding of the subject, are absolutely necessary. These qualifications are possessed by Clouston's work, which is suitable alike for the general physician and the specialist. The advances that have been made in psychiatry in the two years that have elapsed since the presentation of the last edition have been incorporated. There is one thing that always gives a charm to Clouston's works, i. e., his honesty, modesty, and entire candor. It is evident from a perusal of the pages of this edition that Clouston will continue to remain a constant favorite.