STENEOSAUEUS. 



95 



differ in the various species : these differences will be referred to below. The 

 remainder of the cervical series consists of eight vertebrae (text-fig. 35) probably in all 

 cases, though in some specimens one or more may be missing. These, like the atlas 

 and axis, differ from one another in the various species to a considerable degree, 

 particularly in the length of the centrum in proportion to its other dimensions, and in 

 the height of the neural spine. Speaking generally, the centra have slightly concave 

 articular ends, the posterior concavity being the deeper ; the concavity is most 



Text-fig. 35. 



ax. 



Middle cervical vertebras of Steneosaurvs leeclsi : A, from left side ; B, from behind. (E. 3806, i nat. size.) 

 Also of Stcneosaurits durobrivensis : C, from left side ; D, from behind. (E. 3701, | nat. size.) 



a.z., anterior zygapophysis ; dp., diapophysial process ; n.sp.. neural spine ; 

 pp., parapophysial process ; p.z., posterior zygapophysis. 



marked in the middle, the edges being flat or even a little convex in some cases. The 

 <nds of the centra are nearly circular in outline, the vertical diameter being a little 

 the greater; as a rule, the upper border is a little flattened beneath the neural canal. 

 The sides of the centra are strongly concave from before backwards, and near the 

 sharply defined edges of the articular surfaces bear numerous fine plications. The 



