1. The development of the dermal elements of the skull of Lepidosteus osseus has been studied in a series of twelve stages.
2. The homologies of the three small scale-bones of the snout have been established. They are the rostral, nasals, and antorbitals.
3. The ‘maxillary chain’ is shown to be an extension of the infra-orbital series, and the existence of a true maxillary is established.
4. The extent and single origin of the premaxillary are shown, and its unusual association with the supra-orbital basal is discussed.
5. The correct homologies of the opercular series have been established, the recognition of a sub-orbital has been recorded.
6. It is shown that Stensio's complex nomenclature is redundant to a description of the dermal bones of the skull of Lepidosteus osseus.
- Copyright © 1941 by the Company of Biologists Ltd.