v.] 



EDENTA TA. 



zygapophysis (pz) below, develops an articular surface 

 (/z 1 ) which looks upwards and articulates with a corre- 

 sponding downward directed process (az l ) developed on the 

 upper part of the arch of the following vertebra, rather 

 below the metapophysis (///). Thus the vertebra has a 

 process projecting backwards, with flattened articular facets 

 on its upper and under surface, fitting into a deep recess 

 on the anterior edge of the arch of the vertebra behind, 



FIG. 23. Posterior surface of second 

 lumbar vertebra of Great Anteater, . 

 / transverse process ; pz posterior 

 zygapophysis ; /s 1 , fz j . and /z 3 . ad- 

 ditional posterior articular Cicets. 



FIG. 24. Anterior surface of third lum- 

 bar vertebra of Great Anteater, j. 



articular facets. 



and the articulation is now by two zygapophysial surfaces 

 on each side of the arch instead of one. 



In the thirteenth ' thoracic vertebra a third articular facet 

 (PZ*) is developed on the hinder margin of the lamina of 

 the arch, still higher than the last additional one (f>z l ), 

 and separated from it by a deep notch. This looks mainly 

 outwards, and articulates with a corresponding facet (az 2 , 

 Fig 24) on the anterior edge of the arch of the fourteenth 



1 In the Cambridge specimen this description applies to the fourteenth 

 and fifteenth vertebrae respectively. 



