FE03I THE HASTINGS SAXD. 



215 



13 millim. long. Another Tilgate caudal vertebra, later in the series, 

 is about 15 millim. long. It possessed the transverse process and 

 well-developed proccelian articulation ; but the neural arch is greatly 

 shortened and limited to the middle of the centrum, as in some 

 Dinosaurs. The proccelian vertebras of similar size are from Brook. 

 The specimen 36521, however, has the centrum as well rounded 

 from side to side as in existing Crocodiles, and is not referable to 

 this genus. 



It may be interesting to remark that although this is the oldest 

 proccelian Crocodile hitherto described, the British Museum contains 

 a single cervical vertebra, no. 48244, from the Purbeck beds, which 

 has a well-defined proccelian cup, and the cervical neural arch is 

 constructed on the usual crocodilian plan. 



The existence of this form of vertebra in the Purbeck beds 

 accentuates the apparent difference of the cervical articulation for 

 the rib in the Wealden specimen, a difference sufficiently remarkable 

 to make more striking modifications of the skull and pelvis not 

 impossible. 



I am indebted to Dr. Henry Woodward, F.R.S., for the facilities 

 afforded me in studying and describing this specimen. 



EXPLANATION OF FIGURES. 



Plate XII. 



ns, neural spine ; t, transverse process. 



Fig. 7. Slab, showing sequence of dorsal vertebrae of Heterosuchus valdensis 

 Seeley. 



8. Yiew of the same slab, showing the underside of the centrums of the 

 dorsal vertebrae. 



