Xlll 



PHYLUM CHORDATA 



419 



Solenhofen, Bavaria, belonging to the Upper Jurassic period. The 

 Bird (Fig. 1056) was about the size of a Crow, and in both fossils 

 not only are the bones preserved, but also many of the feathers. 



The most striking feature in the organisation of the Bird is the 

 fact that the tail is composed of about 18 — 20 free caudal vertebrae, 

 gradually tapering to the distal end as in a Lizard. The rectrices 

 are arranged in two rows, one on each side of the caudal vertebrae, 

 forming a long tail quite unlike that of any existing Bird. The 

 centra probably had biconcave faces. In addition to cervical and 

 thoracic ribs (which were apparently devoid of uncinates), there 

 were abdominal ribs, like those of Sphenodon and Crocodiles. 



The skull (Fig. 1057) is proportionately large, with rounded 

 brain-case and strong jaws, in each of which is a series of conical 



Fig. 1057. — ArcbseopteryK lithographica. The skull, showing teeth and sclerotic plates. 

 (From Headley, after Dames.) 



teeth lodged in sockets. There is no trace of sternum in either 

 specimen, and the coracoids {co.) are only partially visible : the 

 scapulae (sc.) are slender, curved bones, and there is a U-shaped 

 furcula {cl.). 



Fin. 1058. — Areheeopteryx litbographica. The left manus. c. carpal ; d.l, first digit ; 

 ^, second digit ; 3, third digit ; m. m. metacai-pals ; r. radius ; u. ulna. (From Headley, after 

 Dames.) 



The bones of the upper- and fore-arm are of the normal avian 

 character: only one carpal is certainly known (Fig. 1058, c.) ; it 

 apparently belongs to the distal row, and is closely applied to the 



