Fig. 18.25. 'ITic ancestry of birds. .4, 

 restoration of Omithosuchiis, a small 

 reptile of Triassic time, representative 

 of the group from which mav be traced 

 the descent of dinosaurs, pterosaurs, 

 and other later reptiles, as well as 

 that of birds. /?, the fossil remains 

 of a Jurassic bird, Archaeopleryx, 

 showing clearly the impressions of 

 feathers. Note such reptilian fea- 

 tures as the teeth, the elongate tail, 

 and the free, clawed fingers. C, 

 restoration of Archaeopleryx based on 

 the fossil remains. (.4 and C re- 

 drawn from G. Heilmann, The Oriam 

 of Birds, copyright 1 927 b\- D. Apple- 

 ton and Co., printed by permission 

 of Appleton-Century-Crofts, Inc.; B, 

 after Steinmann and Doderlein, from 

 E. H. Colbert, Evolution of the Verte- 

 brates, copyright 1955 by John Wiley 

 and Sons, Inc., reprinted by 

 permission.) 









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