14 Pyof. H. G. Seek// — On the Genus Ornithocheirus. 



palate, tliougli badly preserved, was convex on eacli side of the 

 median groove, and between the first pair of palatal teeth the width 

 was twenty-two millimetres. The palatal ridges become depressed 

 a little as they approach its anterior termination, and there appear 

 to be a i^air of small pits in front of them, external to the V-shaped 

 termination of the palatal groove. The teeth which formed the 

 anterior corners of the jaw [Fig. 36 (g)] are only indicated by the 

 bases of the crowns, which were circular. Each is fifteen milli- 

 metres in diameter, or about equal to a medium-sized tooth of an 

 Ichthyosaurus, and perhaps as large as any Plesiosaurian tooth. 

 Each tooth is contained in a socket, which approaches within about 

 a millimetre of a lateral wall of the jaw, and within about two 

 or three millimetres of its anterior termination. The bone behind 

 the tooth-socket rounds convexly from the lateral palatal inflation 

 into the external side of the jaw, M'ithout any limiting ridge or 

 angle. This pair of teeth was directed somewhat forward as 

 well as upward and outward, and it may be presumed that the 

 outward angle was determined by the inferior convergence of the 

 lateral walls of the jaw. Behind this pair of teeth, and separated 

 from them by an interspace of five or six millimetres, was another 

 pair, of which only an indication of the anterior wall of the sockets 

 remain. These show that the second pair of teeth were separated 

 by a wider breadth of the palate. The sockets are not directed 

 tipward at quite the same angle, and that on the right side shows 

 the fang to have been imbedded in the jaw for a depth of about 

 tliirty-five millimetres. The bony surface at its posterior fracture 

 is black, rough, and corroded, as though by exposure on the sea- 

 bed, and displays one or two fragments of incrusting shells. The 

 anterior face of the specimen is triangular, formed about a right- 

 angle apparently with the palate, and contains in its upper part the 

 broken stumps of two pre-palatal teeth. This anterior region 

 is about thirty-five millimetres deep, and at its widest part at 

 the outer corners of the palatal tooth-stumps is fully thirty- 

 five millimetres wide. The sides, which converge inferiorly, are 

 about thirty millimetres long, and round into each other in an 

 ill-defined way ; the upper part especially of the lateral wall of the 

 jaw rounds convexly towards the tooth-stumps in its upper part 

 already alluded to, but it is margined by a slight ridge. The superior 

 outline is three-sided, and consists of a middle horizontal portion, 

 with lateral parts sloping outward and downward in front of the 

 palatal teeth. The tooth-stumps on this anterior face [Fig. 3a (p)] 

 are three or four millimetres below the anterior border of the palate, 

 and ai'e separated from each other by an interspace of less than half 

 a centimetre. The bone of this interspace in its upper part is 

 smooth and marked by a relatively wide and moderately deep groove, 

 which dies away towards the palatal margin. The tooth sockets 

 are ovate, probably from the direction of the section of the tooth, 

 one and a half centimetre deep, and over a centimetre wide. They 

 were probably circular, since they are seen to have been directed 

 forward at a greater angle than the palatal teeth. The anterior space 



