328 



DR. ST. GEORGE MIVAET ON THE SKELETON OF [^W- 2' 



tuberculum and capituluin not quite so far apart. The posterior 

 articular surface of the centrum is concave. 



The Sacrum. 



This mass of anchylosed vertebrae (figs. 16, 17, 18, & 19) 

 apparently consists in both species of four lumbosacral vertebra, 

 an indeterminable number of sacral vertebrae, and from five to six, 

 probably seven, uro-sacral vertebrae. 



rs" 



r 



bu 



Lateral aspect of sacrum and pelvis of Psittacus erithacus. 



The Lumbo-sacral Vertebra. 



These four vertebrae are anchylosed together with the ilium (il), 

 and, of course, with the solid mass of the true sacral vertebrae. 



The^T-si lumbo-sacral vertebra seen preaxially exhibits its neural 

 arch, prezygapophyses, neural spine, and transverse processes, each 

 presenting a concave tubercular surface, while outside the base of 

 the neural arch just above the centrum is the capitular cup. The 

 preaxial surface of the centrum is concave, 



