210 PICTURESQUE SKETCHES 



ous land reptiles met with in the oolites, and the 

 singular flying reptiles already described; but, al- 

 though the quarries have been diligently searched, 

 and the evidence carefully collected, there has not 

 hitherto been obtained distinct proof of the presence 

 of birds, and there is no trace, not even the slightest, 

 of any true quadruped. 



The gigantic companion of the megalosaur, during 

 the Wealden period, has received the name of Igua- 

 nodon.* It is known to us by the teeth and a con- 

 siderable part of the skeleton ; but, unfortunately, 

 there has not yet been found any portion of the skull 

 sufficiently perfect to be absolutely identified with 

 the other bones. 



The teeth of the Iguanodon (79, 80, 81) are 

 partly composed of bone, gradually becoming softer 



Fig. 79 Fig. 80 Fig. 81 



IGUANODON. 

 Teeth in different Stages of Growth. 



from the edge inwards, and partly of enamel, by 

 which they are surrounded; the result of this con- 



* Iguana^ a recent West Indian lizard ; oSovs (odous), a tooth : from 

 the resemblance of the teeth to those of the iguana. 



