294 THE BATH OOLITE PERIOD. 



iguanodon, all the articulations are definite, and made so as to 

 correspond to determinate movements in particular directions, and 

 these are such as to be suited for walking. In particular, the femur, 

 by its head projecting freely from the acetabulum, seems to claim 

 a movement of free stepping more parallel to the line of the body, 

 and more approaching to the vertical than the sprawling gait of 

 the crocodile. The large claws concur in this indication of ter- 

 restrial habits. 



But on the other hand, these characters are not contrary to the be- 

 lief that the animal may have been amphibious; and the great vertical 

 height of the anterior part of the tail (see Diagram LXXXIX.) 

 seems to support this explanation, but it does not go further. For 

 the later caudal vertebrae, instead of being much compressed, as 

 in teleosaurus, are nearly circular in the cross section, and are inter- 

 locked by posterior zygapophyses, extended over half, or the whole 

 length of a vertebra. 



"We have, therefore, a marsh-loving or river-side animal, dwelling 

 amidst filicine, cycadaceous, and coniferous shrubs and trees full 

 of insects and small mammalia. What was its usual diet ? 



If ex ungue leonem, surely ex dente cibum. We have indeed but 

 one tooth, and that small and incomplete. It resembles more the 

 tooth of iguanodon than that of any other reptile ; for this reason 

 it seems probable that the animal was nourished by similar vegetable 

 food which abounded in the vicinity, and was not obliged to con- 

 tend with megalosaurus for a scanty supply of more stimulating 

 diet 



