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179 



few modern birds that are characterized, by the absence or vestigeal 

 character of the wings, with corresponding changes in the structure 

 of the sternum (not keeled), coracoid and other bones. They are prob- 



PIG. 112. Archaeopteryx lithographica. X/^[. c, carpel; cl, furcula; co 

 coracoid; h, humerus; r, radius; sc, scapula; u, ulna; I-IV, digits. (From Hegner' 

 College Zoology, after Zittel from Steinman and Doderlein.} 



ably degenerated descendants of originally winged ancestors. The 

 best-known representatives of this small division are the Kiwis of New 



