192 THE STORY OF REPTILE LIFE. 



oldest known bird, it is certainly not the first 

 bird. Whether their remains are ever found or 

 not, there can be no doubt but that yet more 

 primitive types than Archaeopteryx must have 

 existed, and similarly there must have lived 

 more primitive types than the most primitive 

 known dinosaurs Anchisaurus and Zandodon, cf 

 the Upper Trias. Consequently there is no 

 reason why the bird and the dinosaur should 

 not, after all, have been derived from the same 

 incipient stock. That is to say, the mere fact 

 that the oldest-known bird and the most bird- 

 like dinosaurs were contemporaries, or that the 

 wing of the bird is totally different from the 

 fore-limb of these contemporaries, is no proof 

 that the two forms must be of totally distinct 

 origin. The real objection to such an alliance 

 seems to lie in the structural plan of the skull. 

 The dinosaurs exhibit the same wing-like ex- 

 pansions of the hinder-end of the parietal, and 

 splint-like squamosal that is found to obtain in 

 all the members of that great branch of the 

 reptilia, which apparently derive their origin 

 from the Rhyncocephalian stock. Whilst this 

 region of the skull in the birds rather resembles 

 that of the Anomodonts and Chelonia, whether 

 the latter really derive their origin from this 

 stock or not, is a moot point. But there is 

 good reason to believe that the Anomodonts, 

 as we have already pointed out, are direct 

 descendants from the ancient Amphibia. The 

 birds then, perchance, may have arisen from 

 a stem quite distinct from the dinosaurs, though 

 we are as yet in ignorance of the precise nature 



