346 



THE BIOLOGY OF BIRDS 



such as Hesperornis and Ichthyornis, both with a good 

 equipment of teeth, but apart from teeth there is not much 

 more of the reptile in them than we can find in any ordinary 

 bird. 



The rock record shows that there was a time when the 

 highest backboned animals on the earth were Reptiles ; and 



Fig. so. — Restoration of Archaeopteryx. 

 (By kind permission of Mr. W. P. Pycraft.) 



the cumulative evidence in support of the evolution-idea 

 leads one naturally to think of Birds (and Mammals too) as 

 arising from some reptilian stock. Yet the antithesis between 

 flying birds, the creatures of the air, and grovelling reptiles, 

 the creatures of the earth, is so striking that it is only reason- 

 able to inquire into the evidence, apart from the connecting 

 link of Archasopteryx, in support of the conclusion. 



