A general description of the skull of a particularly well-preserved specimen of Daptocephalus leoniceps (Owen) is given and the surface features of the septomaxilla described; it is suggested that this bone may have supported a nostril-closing valve and that D. leoniceps may have been slightly amphibious. The conformation of the bones in the pterygoid region is described and attention is drawn to an arrangement which may prove to be a useful systematic character. A description of the masticatory apparatus is given and its mode of action is discussed, as are the homologies and significance of the labial fossa. The auditory region is described. A description of a small bone, interpreted as an ossified extra-stapes, is given and the position of the tympanum is discussed. The proatlas, atlas and axis are described and a restoration of the neck muscles is made. Some of the bones of the manus are described and the functional significance of a number of the characteristics of the genus Daptocephalus is briefly outlined.