1 Talk Preopercular Edit Fossil Record The preopercular is a bone at the back of the skull. This article is a stub. You can help Fossil Wiki by expanding it. Read more The vomer is one of the unpaired facial bones of the skull. Vomer The nasal bones are two small oblong bones, varying in size and form in different individuals,... Nasal bone The frontal bone is a bone in the skull. Frontal bone Related Categories Categories: Article stubs | Skull Add category