266 THE JBATH OOLITE PERIOD. CHAP. 



of ceteosaurus have no particular affinity with those of crocodile, 

 except in the diapophyses and neural spines. The bodies of the 

 vertebrae are different, especially in the posterior part of the tail, 

 where the hour-glass shape is significant of quite other kindred. 

 And in respect of the processes referred to, the resemblance is not 

 great. The diapophyses are subcylindrical or conical, instead of 

 being flat plates ; and, in the latter part of the tail especially, the 

 excurrent neurapophyses are of quite a different character. 



To those caudal vertebrae of the Wealden, which have been 

 'referred to pelorosaurus and ceteosaurus, the resemblance of our 

 Oxonian fossils is much closer. The four anterior caudals, figured 

 by Mantell as median caudals of pelorosaurus (Phil. Trans. 1850, 



2 



Diagram XCVI. Posterior Caudal Vertebra of Ceteosaurus, from Glympton. One- 

 fifth of nature, i. Seen from above. 2. Seen on the right side. 3. Seen from below. 



Plate XXII.), agree in a general manner with ours from the same 

 part of the tail, but are much shorter, and more quadrate : the 

 zygapophyses differ, but the chevron bones agree in being disunited 

 proximally. 



Still more considerable is the agreement of one of our (posterior) 

 caudals, Diagram XCL, with the curious vertebra described as 

 < median caudal' of pelorosaurus (Phil. Trans. 1850, Plate XXVI.). 

 The cylindrical form of the anterior zygapophysial processes in the 

 Wealden fossil, and their great forward projection, make a dif- 

 ference : in our specimens these processes are not so different from 

 the pattern of the anterior vertebrae. Our vertebrae from Glympton 



