J. B. Lippincott Co. London: Pitman Medical Publishing (Jo. Pp. 203. 32s. The number of useful texts on mental deficiency is small, especially those by psychologists, so that a new volume written by the chief clinical psychologist of the Flower and Fifth Avenue Hospitals, New York, is opened with interest. The author, Harold Michal-Smith, draws a clear picture of the inadequacy of the social se...