434 



MR. J. W. HULKE ON THE SKELETAL 



[Nov. 20, 



With the ascent of the parapophysis on the lateral surface of the cen- 

 trum, the ventral surface of this becomes narrowed and a low keel 

 arises here at its middle. The terminal surfaces of the centrum have a 

 subcircular outline. In vertebrae referred to the anterior region of the 

 thorax, the centrum assumes a cylindroid form. In a few, in which 

 the parapophysis is passing off the centrum on to the neural arch, 

 the antero-posterior dimension of the centrum is slightly less than in 

 the neck, and in the succeeding vertebrae in the posterior part of the 

 trunk. In these last the centrum is nearly cylindric, contracted at 



Fig. 3. 





Cervical vertebrse of Steneosanrus. 



its middle, and dilated at both its ends (fig. 4, p. 435). In the anterior 

 caudal vertebrae the centrum is laterally slightly compressed, its ven- 

 tral aspect cylindroid. The transverse process in these vertebrse is 

 suturally attached in the level of the neuro-central suture, the 

 sutural impression being shared by the centrum and the neurapo- 

 physis. In vertebrae deemed by their smaller size to be situated 

 posteriorly to the above, the centrum is much more compressed later- 

 ally, which, with the flatness of the under surface, gives the centrum a 

 parallelopipedal figure (fig. 5, p. 435). In these vertebrae the 



