Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/272

 complete. In front it is flat; but from the middle of the snout backwards the inner border of the maxillaries and of the palatine bones form a low median ridge, which makes the palate in this part convex transversely.

The praemaxillary sutures form an acute angle open behind, as they do in Steneosaurus rostro-minor, I cannot speak with certainty of the suture between the maxillary palatine plates and the palatine bones ; it seems to be a straight transverse line.

The anterior palatine foramen is small ; it is situated opposite to the interspace between the second and third teeth. The front end of the posterior palatine foramen, angular and narrow, is seen opposite to the penultimate tooth.

It will be recollected that in my last paper I showed that the lower jaw and praemaxilla of this Kimmeridge crocodilian so closely resembled those of Cuvier's second Honfleur Gavial " tete a museau plus court" (Steneosaurus rostro-minor, Geoffroy St.-Hilaire) as to afford a very strong presumption of their specific identity ; and I identified it by means of its teeth with Dakosaurus maximus, Quenstedt. The more rigid comparison which the additional material since acquired has made possible, confirms the opinion thus expressed, that this Kimmeridge crocodilian is really a Steneosaur ; but it also proves it to be a distinct species. Its snout is stouter than that of the two Honfleur Gavials ; the structure of its distal half differs from that which obtains in these and in the Oxford (Shotover) Steneosaur. The number and distribution of the teeth differ also considerably from those in the " tete a museau plus court," which has 22 teeth in each half of the lower jaw, of which 7 are postsymphysial ; while the lower jaw of the Kimmeridge Steneosaur has not more than 15 teeth on each side, and of these at most 4 are behind the symphysis.

For this new Steneosaur I propose the specific name Manselii, in honour of its discoverer : — Steneosaurus Manselii.

Dec. 1869.

Postscript.- — I cannot quite shake off the suspicion that the slender nasals may be present in the Geneva snout, and perhaps also in the Oxford (Shotover) Steneosaur's skull.

Cuvier, in describing the nostril of the Honfleur gavial " tete a museau plus court," says, " Le bord posterieur et superieur donne deux petites preeminences qui je sont pas au Gavial. Les sutures ne sont pas assez marquees pour que je puisse determiner si ces preeminences appartiennent aux maxillaires ou aux intermaxillaires" *.

Dr. Rolleston, also, writing to me about the Oxford (Shotover) skull, says, " Some restitutive plastering has taken place at the nasal opening ; but into it there projects, from behind forwards, in the middle line, an azygos process. What this is the sutures are not, I think, present to show ; but you will judge."


 * Ossemens Fossiles, tome v. 2 e partie, p. 153.