266 ZOOTOMY. 



processes increasing in size from the first lumbar vertebra 

 to the last, and turning forwards ; the hypapophysis, a 

 short flattened process from the under surface of the 

 centrum of the second and third ; and the anapophysis, 

 a small pointed process, projecting backwards from the 

 posterior edge of the neural arch beneath the posterior 

 zygapophysis. 



21. The sacral vertebrae: these are much like the 

 lumbar, but have smaller metapophyses, and no anapo- 

 physes or hypapophyses. In the first the spine is usually 

 directed forwards, in the second it is vertical, and in the 

 third and fourth directed backwards. The first and second 

 only give attachment to the hip-girdle, for which purpose 

 they are provided with great expanded lateral plates with 

 roughened edges, which answer to sacral ribs. 



22. The caudal vertebrae, at first like the sacral, but 

 gradually diminishing in size and complexity until they are 

 reduced to mere centra. 



23. The last (seventh) cervical vertebra : it somewhat 

 resembles the anterior thoracic, but the transverse process 

 has no facet, and the centrum a demi-facet only on its 

 hinder edge. The centrum also is so altered in shape that 

 its anterior face looks downwards as well as forwards, and 

 its posterior face upwards as well as backwards. 



24. The third to the sixth cervical vertebrae : these 

 have the centrum with its anterior face looking downwards and 

 forwards, and its posterior face upwards and backwards ; the 

 transverse processes are divided into two parts, one of which 

 projects directly outwards, while the other (inferior lamina) 

 forms a flat irregular plate, attached along the whole infero- 

 lateral edge of the centrum. An aperture, the vertebrar- 

 terial canal, perforates the base of the transverse process, 

 and, during life, transmits the vertebral artery ( 250). 



