Abstract
Among 82 temporal bones of baboons, investigated in histological sectional series, 24 (29.5 percent) exhibited histopathological changes. The latter were tabulated after preceding anatomical remarks given as a help to interpret the morbid anatomy. Of surgical consequence, by absence of a sub-iculum is the open niche of the round window offering direct access to the spaces of the cochlea. This advantage is counteracted by the structure of the external auditory canal which, as an obstacle, must be eliminated to make the deeper regions thus accessible.