76 ANIMALS OF THE PAST 



of departure from other vertebrates, is yet to be 

 discovered ; at one time it was considered that 

 they were the direct descendants of Dinosaurs, 

 or that at least both were derived from the 

 same parent forms, and while that view was 

 almost abandoned, it is again being brought for- 

 ward with much to support it. It has also been 

 thought that birds and those flying reptiles, the 

 pterodactyls, have had a common ancestry, and 

 the possibility of this is still entertained. Be 

 that as it may, it is safe to consider that back 

 in the past, earlier than the Jurassic, were creat- 

 ures neither bird nor reptile, but possessing 

 rudimentary feathers and having the promise 

 of a wing in the structure of their fore legs, 

 and some time one of these animals may come 

 to light ; until then Archseopteryx remains the 

 earliest known bird. 



In the Jurassic, then, when the Dinosaurs 

 were the lords of the earth and small mammals 

 just beginning to appear, we come upon traces 

 of full-fledged birds. The first intimation of 

 their presence was the imprint of a single feather 

 found in that ancient treasure-house, the Solen- 

 hofen quarries ; but as Hercules was revealed 



