392 CRETACEOUS REPTILES. 
in ordinary Lizards, but rather longer and more slender. The thin base of the 
neural spine extends along the middle of the summit of the entire arch; the 
sides of which slope downwards and outwards more gradually, i.e. do not curve 
outwards so suddenly as in the Iguana and Cyclodus. The short convex diapo- 
physis (d) supporting the rib is developed from the side of the fore-part of 
the centrum beneath and a little behind the anterior zygapophysis. I excavated 
the chalk beneath the seventh vertebra, and exposed a short compressed inferior 
spine projecting downwards from the middle of the hinder half of the centrum. 
The ribs are hollow, as in the Cyclodus* and in Ophidians. The long pleur- 
apophyses of the twentieth and succeeding vertebre are more compressed than in 
the Iguana and Cyclodus: they are less regularly or gradually curved: the com- 
paratively straight middle portion after the first slight bend is too constant in the 
ribs of the fossil not to be natural: this shape of the ribs indicates the abdomen 
to have been more compressed, as the number of vertebrae shows it to have been 
longer than in the Iguana or Cyclodus. The twenty-sixth vertebra is dislocated : 
the two following are turned upon their side and expose the under part: here the 
inferior spine has disappeared: the surface is smooth, slightly punctate, gently 
concave lengthwise, convex transversely. Figure 2 gives a direct side-view, 
magnified, of the best-preserved ramus (the left) of the jaw: below, in outline, of 
the natural size ; above, magnified. The extent and upward curve of the coronoid 
piece (c) most resembles that in the Varanus (Cuvier, loc. cit. pl. 16. fig. 8, ¢) ; 
but in this genus it is relatively shorter than in the Dolichosaurus, and in other 
recent Lacertians it is still shorter and more pyramidal in shape. The extent 
of the surangular (30), and its length behind the coronoid, are lacertian charac- 
ters: but the outer surface is divided by a longitudinal ridge or angle into an 
upper and a lower facet, the upper one being slightly excavated: the enameled 
crowns of the last four teeth show a simple obtuse shape; they are chiefly re- 
markable for their small proportional size. The two dentary bones meet at an 
acute angle ; that on the right side joins a supra-angular piece which is continued 
back to near the articular surface. Allowing a symphysis of the ordinary 
lacertian proportions, the length of the under jaw may be estimated to have 
been four centimeters (1 inch 7 lines), or equal to between four and five dorsal 
vertebre. 
Parallel with the eighteenth, nineteenth and twentieth vertebre lie the remains 
* The vertebral ribs (pleurapophyses) are probably hollow in other Lacertians, but I cite only the 
genus in which I have found them so in the present comparison. 
