Since the discovery of Spirochaeta pallida, a number of diseases caused by the spirochete have been described, with special reference to localization in various parts of the body. Castellani, for instance, described a bronchial spirochetosis, and Vincent a spirochetosis in association with the fusiform bacillus, mainly of the mouth and pharynx. Since 1916, Troisier and Boquien have studied a meningeal spirochetosis caused by the spirochete of Inada-Ido. The authors describe the pathology and pathogenesis of the disease, the clinical picture, the diagnosis and the differential diagnosis, with special reference to the agglutination of blood and cerebrospinal fluid. One chapter is devoted to experimental meningeal spirochetosis. The book is well written and well illustrated.