Note on the Cranial Characters of a large Teleosaur from the Whitby Lias preserved in the Woodwardian Museum of the University of Cambridge, indicating a new Species, Teleosaurus eucephalus

Abstract

T he Woodwardian Museum of the University of Cambridge has long contained the cerebral region of the skull of a large Teleosaur from the Lias of Whitby, which differs in important characters from the Teleosaurs hitherto described, and adds some interesting points to our knowledge of the cranial characters in this extinct suborder of animals. Attention was briefly drawn to the specimen at p. 121 of my ‘Index to the Fossil Remains of Reptilia &c. in the Woodwardian Museum’ 1869. The skull has been transversely fractured anteriorly, posterior to the suture between the parietal and frontal bones, so that no part of the frontal region is preserved, and therefore no indication is given of the anterior expansion of the skull beyond the long temporal fossæ. The crest of the parietal bone appears to have been more than usually wide and strong, but that, too, is imperfectly preserved. The quadrate and squamosal bones are broken away at the sides; the base of the occipital region is fractured, and the pterygoid bones are absent; but the very imperfections of the specimen led to its being sawn through in the median line, so as to display a vertical section of the brain-case. Care has been taken to make the section so as to throw light on the lateral modifications of the brain-case; and I now venture to submit to the Geological Society some account of the characters thus displayed. In existing Crocodiles the brain-case is relatively small, owing to the shortness of the parietal