IGUANODON 
<272 
rior surface is divided longitudinally into three or 
more slightly concave parts, by obtuse ridges, of 
which the most prominent one is situated rather 
towards one side. In the young teeth, seldom 
more than one ridge occurs, dividing the surface 
into two unequal parts ; but in some examples. 
TEETH OF THE IGUANODON. 
1. This specimen shows the crescent-like markings on the enamel, 
described above. 
2, 3. The tooth of a young animal, in which the point is but little 
worn. 
4, 5. A tooth of an adult, in which the crown of the tooth has 
suffered considerably from detrition. 
