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HANDBOOK OF ANATOMY 



The Coccyx consists of four rudimentary vertebras, which are- 

 generally fused together, and often fused with the sacrum. 



Special Vertebrae. 



The First Cervical vertebra, or Atlas, differs from the typical 

 vertebra?. It consists of a ring of bone supporting laterally, 

 the lateral masses which articulate above with the condyles 

 of the occipital bone, and below with the second cervical 

 vertebra. Posteriorly, it has a rudimentary spine, and on the 

 posterior surface of the anterior arch is a small facet for 

 articulation with the odontoid peg of the axis, or second cervical 

 vertebra. The transverse processes, similar to those of the- 

 other cervical vertebras, are attached to the lateral masses. 



Atlantal Facec 

 ^ Odontoid Process 



Groove for Transverse Ligament 



Superior Articular Process 

 Superior 

 Notch 



I Inferior 

 Notch 

 Costo-trans verse Foramen 



Spine 



Lamina 



Inferior Articular Process 



FIG. 29. Axis. 



The Second Cervical vertebra, or Axis, has the odontoid! 

 process projecting from the upper surface of its body, which 

 articulates with the anterior arch of the atlas. The superior 

 articular surfaces are large and nearly circular, to correspond 

 with the inferior articular processes of the atlas. 



The Seventh Cervical vertebra is called the vertebra 

 proininens owing to the spine, whiclj ends in a broad, single 

 tubercle, and is markedly prominent at the root of the neck. 



The Dorsal, or thoracic, vertebras are characterized by having 

 articular facets on their bodies for the heads of the ribs, and 



