In the present edition of this companion volume to the equally well known index of differential diagnosis, of which French is editor, no alterations in plan or format have been made. The number of individual contributors has been reduced from ninety-one to seventy-eight. A few subjects make their appearance for the first time, the principal ones being bone setting, rat bite fever, sebaceous cysts and syndactyly. Few of the treatises seem to have been completely rewritten—an unfortunate fact in certain instances, notably pneumonia. The book must continue to disappoint those who wish to have an unprejudiced and inclusive therapy presented in a specific fashion.