The order of the portion of bones in the skull roof of Oedaleops and "Eothyris parkeyi" conforms to a basic pattern in primitive reptiles and is shared with various groups such as millerosaurs and captorhinomorphs, and ophiacodonts. The major distinguishing features of the skull are that it possessed a pair of long, large, fang-like teeth on each side of the upper jaw. The use for these teeth is not known, but "Eothyris parkeyi" might have used them to eat small prey. All teeth in its mouth were sharp, with all but the enlarged four fangs being small and short. The skull is short and broad, two features which suggest that "Eothyris parkeyi" had a snapping, rapid bite.