DINOSAURS 159 
illustrious Baron Cuvier. Let us begin with the teeth, since 
they were the first part of the monster brought to light. 
The first specimens of the teeth of Iguanodon were found by 
Mrs. Mantell, in 1822 (see Fig. 53), in the coarse conglomerate 
of certain strata in Tilgate Forest, belonging to the Cretaceous 
period (see Table of Strata, Appendix I.). Dr. and Mrs. Mantell 
subsequently collected a most interesting series of these remark- 
able teeth (which, for a time, puzzled the most learned men of 
Fic. 53.—Tooth of Iguwanodon, with the apex slightly worn. (From the 
Wealden Beds of Tilgate Forest. Natural size.) 1. Front aspect, showing the 
longitudinal ridges and serrated margins of the crown. 2. View of the back, or 
inner surface of the tooth. a. Serrated margins. 6. Apex of the crown worn by use. 
the day), from the perfect tooth of a young animal, to the last 
stage, that of a mere long stump worn away by mastication, 
In external form they bore a striking resemblance to the grinders 
of herbivorous mammals, and were wholly unlike any that had 
previously been known. The first specimen that arrested his 
attention was a large tooth, which, from the worn surface of 
its crown, had evidently once belonged to some herbivorous 
animal. In form it so entirely resembled the corresponding 
