14 



Mantellian Museum at Lewes. 



pared with the relative size of the teeth of the MammglUa. 

 To form some notion of the immense magnitude of the 

 animal, it may be useful to mention that I measured the 

 circumference of the condyle, or joint, of a thigh bone in the 

 museum, and found it to be 35 inches ! and the thigh bone of a 

 larger animal, at a distance from the condyle, measured 25 in. 

 in circumference. Mr. Mantell justly observes, in his interest- 

 ing work on the fossils of Tilgate Forest, " Were this thigh 

 clothed with muscles and integuments of suitable proportions, 

 where is the living animal with a limb that could rival this 

 extremity of a lizard of the primitive ages of the world ? " 



In the teeth which have been little worn the summit is 

 pointed, as otjig. 1. a, which represents the front view of the 



perfect tooth of a young animal ; but as the animal increases 

 in size and age, the point becomes worn down, as repre- 

 sented at b, which is the front view of a full-grown tooth 

 of the natural size. The anterior surface of the tooth b is 

 divided longitudinally into slightly concave furrows, by obtuse 

 ridges, the most prominent of which is generally on one side. 

 In the young tooth (a) seldom more than one ridge occurs, 

 dividing the surface into two unequal parts. As the animal 

 advances in age, the furrows become obliterated by use and 

 the front worn down, as represented at c. With a further 

 advance of age, the tooth is more and more worn down, till it 

 becomes a mere bony plate. Tliis wearing away of the crown 

 of the tooth may be traced in every stage of its progress, 

 among the specimens in Mr. Mantell's museum. Baron Cuvier 

 observes that the process by which these changes have been 



