Dinosauria. 
PLATE 18. 
Portions of the upper and lower jaws of the Iyuanodon: nat. size. 
Fig. 
1. The dentary part of the lower jaw of a large, probably full-grown Zguanodon : 
nat. size. 
From the Wealden of Tilgate, Sussex. In the British Museum. 
2. The outer side of a portion of the back part of the left superior maxillary bone of 
a probably full-grown Zgwanodon: nat. size. 
3. The inner side of the same specimen. 
4. The cut surface of a vertical section taken through the fore part of the same 
specimen. 
From the Wealden near Brook-point, Isle of Wight. In the British Museum. 
