It functions to transmit sound from the eardrum to the inner ear. It is the only middle ear bone in amphibians. Many of the bones of the dermatocranium are reduced or absent. The area under the eyes lacks bones when a frog blinks the eyes actually protrude into the oral cavity. The 2 occipital condyles form from the exoccipitals.
Many reptiles have an opening - the parietal foramen which houses the parietal eye.
New in this group are openings in the temporal area. These are bordered by bony arches. Only the anapsids lack this arrangement. In synapsids the single temporal fossa has an arch - the zygomatic arch which is made from the squamosal and jugal bones. This arrangement is still found in mammals.