Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/312

 218 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. POSTPONED PAPER. On DAKOSAURUS from the Kimmeridge Clay of Shotover Hill. By J. Wood Mason, Esq., F.G.S. (Read Nov. 25, 1868*.)

Early in the spring of 1866 I obtained from the Kimmeridge Clay of Shotover-hill, near Oxford, four entire teeth and one portion of a tooth of Dakosaurus, which is now for the first time described and figured as a British genus.

The only description of this reptile with which I am acquainted is to be found in Quenstedt's 'Der Jura†.' This author, after mentioning the circumstance of his having described it in a former work under the name of Megalosaurus, states that the only part of the skeleton known is a portion of a lower jaw containing six teeth, which are implanted in distinct sockets (Alveolen): a detached tooth, figured in the work referred to, well expresses the general characters given below, even to the crenulation of the trenchant margins.

Fig. 1. Fig. 2.

Posterior view of largest tooth of Dakosaurus.

a. Anterior view of tooth of Dakosaurus.

b. Portion of ridge of same, highly magnified to show crenulation.


 * For the discussion on this paper see p. 16 of the present volume.

† P. 785, Atlas, tab. 97. fig. 11.