AXIAL SKELETON OF THE STRUTHIONIDJE. 



21 



SACRUM OF EMU (natural size). 

 Fig. 16. 



pi 



Ventral view. (Specimen No. 1358 a.) 



The thirty-second and thirty-third vertebrse are about equal in size. They closely 

 blend together, and together send down a thick process, which ankyloses with the 

 preacetabular part of the ilium, ischium, and pubis. 



The thiHy-foiu-th (or eighth lumbar) vertebra has no transverse process visible on its 

 ventral aspect. It may therefore be reckoned as a lumbo-saceal vertebra. Its ventral 

 surface is medianly somewhat keeled axially. An extra, or ninth, lumbar vertebra is 

 intercalated in some skeletons. 



SACRUM AND PELVIS OF EMU (i natural size). 

 Fig. 17. 



Vertical antero-posterior section. (Specimen No. 13b7.) 



THE SACEAL VERTEBR.^'. 



The thirty-fifth, thirty-sixth, and thirty-seventh vertebrte all send out smiiU 

 transverse processes to abut against the postacetabular part of the ilium. These pro- 

 ' The sacral vertebrae are reckoned as three in number, only from analogy with Struthio. 



