The great burst of investigations of the thymus over the last ten years certainly justifies a monograph on those aspects of its relation to various clinical problems. The subject matter reviewed essentially covers the structure and function of the thymus as well as the pathological changes in various diseases. The former subject is mainly discussed with the results of animal experiments while the latter is summarized with illustrations of the clinical experiences which had been termed "Experiments of nature."
For the sake of the clinical staff who are interested in the thymus, the authors have included chapters on the diagnostic approach of various diseases involving the thymus.
Both Drs. Mackay and Goldstein have made important contributions to the elucidation of the thymus function, especially the contributions to knowledge of humoral factors produced by this organ. Such factors may play a role in the pathogenesis of myasthenia gravis, even though evidence