162 ORGANIC EVOLUTION CONSIDERED 



the scapula and the wings — and remember that in 

 the Jurassic they were already separated into several 

 genera, it is -evident that if they were evolved they 

 had existed long before the Jurassic, and yet no trace 

 of them has been found earlier than the Jurassic, 

 although the rocks contain abundant fossils of other 

 animals. We have no direct evidence showing the 

 evolution of their wings, and we are left, as usual, to 

 assume the fact. 



It might be supposed that Pterodactyls were the 

 ancestors of birds, but evolutionists claim that this is 

 not the case. 



It is admitted that the evolution of birds from rep- 

 tiles involves great difficulties. There are two divis- 

 ions of the class of birds: the struthious birds, includ- 

 ing the ostrich, emeu, cassowary, apteryx, which 

 have no keel on the breast bone; and the carinate 

 birds, which have a keel. 



Some think that the carinate birds might have been 

 derived from the Pterodactyls, but that the struthious 

 birds could not have had this origin. It is thought, 

 however, that the latter might have been evolved 

 from Dinosauria, which had no wings. 



This would give to birds two separate origins, a 

 thing which their general similarity of structure for- 

 bids. On the other hand, unless birds were derived 

 from Pterodactyls, how can we account for their vari- 

 ous peculiar points of resemblance; and if struthious 

 birds were not derived from Dinosauria, how can we 

 account for their special points of similarity? The 

 above difficulty has not been satisfactorily explained. 

 Mivart has dwelt on it at length.* 



Mivart says that "Prof. Huxley seems inclined to 

 cut the Gordian knot by considering the shoulder 



* See Genesis of Species by Mivart, p. 83, et. seq. 



