2 26 THE HISTORY OF CREATION. 



These colossal reptiles, which attained a length of more than 

 fifty feet, are the largest inhabitants of the land which have 

 ever existed on our globe ; they lived exclusively in the 

 secondary epoch. Most of their remains are found in the 

 lower cretaceous system, more especially in the Wealden 

 formations of England. The majority of them were fearful 

 beasts of prey (the Megalosaurus from twenty to thu-ty, 

 the Pelorosaurus from forty to fifty feet in length). The 

 Iguanodon, however, and some others lived on vegetable 

 food, and probably played a part in the forests of the chalk 

 period similar to that of the unwieldy but smaller elephants, 

 hippopotami, and rhinoceroses of the present day. 



The Beaked Reptiles (Anomodontia), likewise also long 

 since extinct, but of which very many remarkable remains 

 are found in the Trias and Jura, were perhaps closely related 

 to the Dragons. Their jaws, like those of most Flying 

 Eeptiles and Tortoises, had become changed into a beak, 

 which either possessed only degenerated rudimentary teeth, 

 or no teeth at all. In this order, if not in the preceding one, 

 we must look for the primary parents of the bird class, which 

 we may call Bird Reptiles (Tocornithes). Probably very 

 closely related to them was the curious, kangaroo-like 

 Compsognathus from the Jura, which in very important 

 characteristics already shows an approximation to the 

 structure of birds. 



The class of Birds (Aves), as already remarked, is so 

 closely allied to Reptiles in internal structure and by 

 embryonal development, that they undoubtedly originated 

 out of a branch of this class. Even a glance at Plates II. 

 and III. will show that the embryos of birds at a time 

 when they already essentially differ from the embryos of 



