Abstract
The fiber arrangement of the intermediate fibrous layer of the guinea pig tympanic membrane was observed by scanning electron microscopy. The intermediate fibrous layer consists of radial fiber bundles and not-radially oriented fiber bundles. The latter is subdivided into four groups; parabolic, circular, oblique fibers and the annular ligament. The directional organization of those fiber bundles is demonstrated. The oblique fibers consist of two distinct fiber groups, termed as oblique ascending and oblique descending fibers. The distribution of the non-radial fiber bundles is demonstrated under three dimensional surface views and discussed concerning the vibratory pattern of the tympanic membrane.