CHAPTER XIII 



THE PEDIGREE OF BIRDS 



The Oldest Known Bird. § 2. Affiliation of Birds to Reptiles. 

 § 3. Resemblances in the Development of Birds and Reptiles. 

 § 4. From which Reptilian Stock ? § 5. Speculations. § 6. Primi- 

 tive Toothed Birds. § 7. Running Birds. § 8. Flying Birds. 

 § 9. The Process of Evolution. 



§ I. The Oldest Known Bird 



The first remains of an undoubted bird are those of Archse- 

 opteryx in the lithographic stone strata of Bavaria, which are 

 referred to the Jurassic age. Two fine specimens are known, 

 and these show certain reptilian affinities — an indication of 

 the affiliation of birds to some reptilian stock. The following 

 may be mentioned : teeth in both jaws (three visible above 

 and thirteen below) ; a long tail like a lizard's with about 

 twenty vertebrae ; a set of " abdominal ribs " — subcutaneous 

 ossifications running across the ventral surface of the 

 abdomen — similar in a general way to those in the crocodile 

 and some other reptiles ; three clawed fingers and the palm 

 or metacarpal bones separate from one another — a sort of 

 half-made wing in short. Yet the bird-like characters of 

 Archaeopteryx are plain enough, e.g. the feathers which have 

 left their imprint on the fine-grained stone, and the general 

 nature of skull, hip-girdle, and hind legs. It was about the 

 size of a crow. 



Although Archaeopteryx is much too specialised to be 

 regarded as the first bird, it seems fair to say that it was a 

 primitive bird with some striking reptilian features. There 

 are other extinct birds with indubitably primitive characters, 



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