52 



FOSSIL REPTILIA OF THE 



below the proximal end : the whole thickness of the bone, within the compact outer 

 wall, being occupied by a coarse cancellous structure. 



Fig. 8. 



Fig. 10. 



Fie. 9. 



Fig. 11. 



Proximal end and section of shaft of a metatarsal bone of Polyplychodon. 



Of a fragment, 12 inches long, of the proximal portion of a metatarsal bone, 

 figure 8 gives the contour of the articular end ; and fig. 9 of the fractured end of the 

 shaft; the dotted outline indicates where the outer crust of the wall prevented an 

 exact figure of the contour being made ; but the shaft of the bone seemed to have been 

 flat on that side. 



A fourth fragment of a long bone measured 10 inches in length. Figure 10 gives 

 the contour of the proximal articular end of this bone (the outer wall having scaled 

 off). Figure 11 is the contour of the fractured end of the shaft, 5 inches beyond the 

 articular end. It is occupied by a coarse cancellous structure throughout. 



There remain to be noticed some less perfect fragments of huge flat bones im- 

 bedded, or indicated by their impressions, in masses of the Green-sand Rock. In three 

 of these I recognise the ilia, ischia, and pubes : they are broader than in the Crocodiles, 

 but would be conformable to the Crocodilian type, if the cartilaginous parts of some of 

 those bones in the recent species were ossified : by this greater extent of ossification 

 of the large fossils in question, the pubis and ischium approach somewhat to the 

 Plesiosaurian type. The ilia are imbedded in the same block of stone : they are flat, 



