This publieation summarizes an initial unpublished report (1971) on diagnostie eriteria in dry bones. The relevant study was made in 22 medieal museums in Europe, England and Seotland between 1966 and 1969. About 670 dry bones were reeorded by over 2000 photographs. Emphasis is plaeed on ehanges for whieh diagnostie eriteria are proposed rather than on those for whieh diagnostie problems remain. The ehanges studied were maeroseopieal not mieroseopieal. This is not areport on the pathological ehanges in dry bones in medieal museums, but a statement on "Diagnostic eriteria of syphilis in dry bones" and of eertain other prevalent ehanges, and their eauses, whieh are needed for differential diagnosis. 'Syphilis' as used here usually refers equally to the 'treponematoses' whieh inc1udes yaws and treponarid. It is intended as a eomprehensive guide for archaeologists and anthro- pologists, and as an instrument of preeision for osteo-arehaeologists. It is not a manual of pathology, although pathologists may be interested in this revival of the dying skill of diagnosis of disease in dry bones. All reeords, written, photo graphie and radiographie, together with the initial 120,000 word report, have been deposited in the Department of Morbid Anatomy, Institute of Orthopaedies, London, where they will be available for study. Abrief introduetion to this study has been published (Haekett, 1975). I would like especially to thank the President of the Heidelberger Akade- mie der Wissenschaften, and Doktor H. Götze of Springer-Verlag, Heidelberg, for the publieation of this monograph.