THE \ ERTEBRAL COLUMN 



157 



a somewhat massive basal portion, the vertebral body (corpus 

 vertebrae) or centrum, and of a dorsal, vertebral arch (arcus verte- 

 brae). The two portions enclose a large aperture, the vertebral 



Fig. 82. Representative vertebrae: A, atlas, anterior surface; B, epistro- 

 pheus, lateral surface; C. fifth cervical vertebra, anterior surface; D, fourth 

 thoracic, lateral surface; E, F, second lumbar vertebra, anterior and lateral 

 surfaces. 



a.a, anterior arch of atlas; a. p., posterior arch of atlas; a. v., vertebral 

 arch; c.v., vertebral body; d, dens epistrophei; f.a.a., anterior articular facet 

 of epistropheus; f.a.s., superior articular pit of atlas; f.a.s., superior articular 

 facet of epistropheus; f.c.i., inferior costal demifacet for head of rib; f.c.s., 

 superior costal demifacet: f.c.t., costal facet of transverse process; f.d., fovea 

 dentis; f.i., intervertebral foramen; f.tr., foramen transversarium; f.v., fora- 

 men vertebrale; 1., lamina of vertebral arch; m.l., lateral mass of atlas; 

 p.a., accessory process of lumbar vertebra; p.a.i., inferior articular process; 

 p.a.s., superior articular process; p.m., mamillary process; p.s., spinous 

 process; p.s. a., anterior spinous process; p.t., transverse process; p.tn., tri- 

 angtilar process; r., radix of vertebral arch; r.a., r.p., anterior and posterior 

 radices of transverse process of cervical vertebra; t.a., t.p., anterior and 

 posterior tubercles of atlas. 



foramen (foramen vertebrale). The successive foramina form an 

 almost complete tube, the vertebral canal (canalis vertebralis), 

 for the accommodation of the spinal cord. 



