356 PROFESSOR OWEN, ON THE RHYNCHOSAURUS. 



Through the kind and zealous attention of Dr. Ward to the quarrying 

 operations in his neighbourhood, various fossils were from time to time 

 secured and transmitted to me, which at length enabled me to form 

 a clear opinion of the nature and affinities of the animal in question. 

 I say of the animal that impressed the sands with its feet, because, with 

 respect to the bones, Dr. Ward observes in his letter accompanying them : 

 " As they have always been found nearly in the same bed as that impressed 

 by the footsteps I have described, I am induced to believe that these are 

 the bones of the same animal:" and in this opinion, from the correspondence 

 of size between the bones and foot-prints, and from the circumstance 

 of the absence of other observed bones or foot-prints in the same quarry, 

 I entirely coincide. 



The vertebrae, to which my attention was first directed, proved the 

 species to belong to the Lacertine or lower division of the great Saurian 

 group of reptiles*. These bones will be first described. 



Vertebree. — Both surfaces of the centrum are concave and are deeper 

 than in the biconcave vertebrae of the extinct Crocodilians ; the texture 

 of the centrum is compact throughout. In the dorsal series the two 

 lateral surfaces join the under surface at a nearly right angle, the transverse 

 section presenting a subquadrate form, with the angles rounded off: the 

 under surface and sides are regularly concave longitudinally. 



The neural arch is anchylosed with the centrum, without trace of suture, 

 as in most Lizards ; it immediately expands and sends outwards from 



* An extended survey of the modifications of this class of Vertebrata from their first appear- 

 ance on the Earth's surface to the present time, is necessarily attended with different views of 

 their classification than can be derived from an acquaintance, however close, with existing 

 species only. I propose to divide the Reptilia into eight orders: viz. Dinosauria, Enalio- 

 sauria, Crocodilia, Lacertili a, Pterosauria, Chelonia, OPHiDiA.and Batrachia. They 

 are here enumerated in the descending scale of organization. The Saurian division was repre- 

 sented of old by reptiles manifesting the crocodilian grade of structure, under a rich variety of 

 modifications, constituting, besides the typical and still represented groups, two other orders, 

 now wholly extinct ; it has since subsided into a swarm of small Lacertians, headed by so few 

 examples of the Crocodilian or Loricate species, that it is no marvel such relics of a once pre- 

 dominating tribe should have found a humble place in Linne's System of Nature, as co-ordinate 

 members of the genus Lacerta. 



