Abstract
The membranous labyrinth of normal guinea pig was studied by the electron microscope, and the following several findings were reported
1. Shape and internal structures of hairs. Relationship of hairs to cuticula and tectorial membr-ane.
2. Smooth and rough surfaced endoplasmic reticulum, and arrangement of mitochondria within external and internal hair cells.
3. Fine structures of supporting cells, reticular membrane, Hensen's cell, tectorial membrane crista spirale, basilar membrane and mesothelial cell.
4. Postmortal changes of hair cells and supporting cells of the organ of corti.
5. Innervation and internal structure of the peripheral fibers of acoustic nerve.
6. Difference of shape and internal structures of nerve end organ at the external and internal hair cells.
7. Flow of the nutritional material within the organ of corti.
