6 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Noy. 10, 
and I was almost disposed to admit their identity with those of the 
latter genus, after the rapid examination which was alone possible at 
the meeting of the British Association at Norwich. A more critical 
comparison, however, has convinced me that the teeth of this reptile 
are perfectly distinct from those of the great Wealden Dinosaurian. 
A large postfrontal separates the orbit from the temporal fossa, 
and appears to have united with the jugal, of which only an impres- 
sion remains. A prefrontal is distinguishable at the upper and an- 
terior part of the orbit. Beneath and behind it, lies a broken but very 
large and curiously curved acrymal (Za), which is deeply grooved 
upon its outer surface, the outer and posterior lip of the groove 
being much shorter than the inner and anterior lip. An ascending 
process of the maxilla seems to have articulated with the posterior 
and inferior end of the lacrymal. The anterior margin of this 
lacrymal process of the maxilla, the superior margin of the body of 
the maxilla in front of it, and the posterior margin of that broad 
nasal process of the maxilla which ascends behind the premaxilla 
are all smooth, and evidently natural, free edges. Hence there must 
have been a considerable preelacrymal vacuity (a) in the walls of the 
face. The postfrontal sends a long process backwards, outside an 
anterior prolongation of the squamosal, the two combining to form the 
supratemporal zygoma. An impression on the matmx proves that 
there was a strong infratemporal zygoma formed by the jugal and 
quadrato-jugal ; and on the left side the under part of this is visible. 
Remains of large sclerotic plates lie in the orbit. The hinder face 
of the distal half of the quadrate bone is displayed upon the left 
side (fig. 4, Qu). It is a very strong bone, the articular surface of 
the condyle measuring not less than half an inch from side to side. 
The occipital face of the skull is much injured, but it was evi- 
dently directed almost perpendicularly to the upper face. The left 
parotic process is well displayed, and is proportionally large, being 
half an inch long and 0-3 inch wide. The base of the skull ex- 
hibits the injured basioccipital region, and the more perfect basi- 
sphenoid, which possesses two strong, divergent, basipterygoid pro- 
cesses. Against the outer ends of these the strong pterygoid bones 
abut. These are not at all unlike the corresponding bones in an 
Iguana. The central part, or body, of the bone is very strong; and 
it sends backwards and outwards a deep, laterally compressed plate, 
which abuts against the inner side of the quadrate bone. The body 
of the pterygoid bone is very strong, and produced vertically. An- 
teriorly and externally it becomes connected, by a transverse bone, 
with the maxilla. A small palatine bone is seen on the left side 
in front of the pterygoid. The pterygoid is, in many respects, like 
that bone in the existing Jguane ; and this specimen shows very 
clearly that the Dinosauria had a Lacertilian and not a Crocodilian 
arrangement of the pterygoid and palatine bones. Only the right 
ramus of the mandible can be seen; and the symphysial end of that 
is broken away. But what remains is nearly in place, and shows 
that the angular process was relatively small, while the coronoid 
rises abruptly, in front of the articular surface, to the height of an 
