This comprehensive textbook has been a standard in its field for a generation. The present edition stands as a monument to its senior author, Dr. Oliver S. Ormsby, who guided the book through eight editions, but who died on April 9, 1954, while the proofs of this edition were being read. Under the continuing authorship of Dr. Hamilton Montgomery, co-author of the last three editions, and four new contributors, Drs. Edward De-Lamater, Eugene Farber, Robert Kierland, and Walter Lobitz, the book maintains its standards of excellence. Extensive revisions have been made in this edition. The chapter on the chemistry and physiology of the skin has been expanded, and the results of recent investigations in this field have been included in many sections of the book. New concepts of melanin formation are presented along with advances in the therapy of pigmentary disorders. Recent studies on the L. E. phenomenon, which have