available, such as those by Vosteen (1961) on the biology of the inner ear, Beckmann (1962) on deafness in children, and Lehnhardt (1965) on industrial otopathies. The text contains only brief references to these, followed by more detailed expositions of what has come to light in the interim. In keeping with the broadness of the topic the list of references is extremely long, though we are aware that it is still not absolutely comprehensive. It is intended to give readers interested in specific topics an idea of the literature available and to provide a point of departure for further work. Scientific research is progressing and news insights appearing so fast, however, that the topicality of the material will be limited.