teriorly with the spinal 



and are finally lost upon the lateral i 



I e portions of : 

 well developed in the up] 

 are designated as the lateral 

 large car shaped arti< ulai 

 pelvic bones, and o< riiefly 



upon the third sa< ral 

 rough impression, the sacral tub< 

 named part of the pelvic • 

 the pelvic surfa< e then 

 terminalis), whit h separates th 



The upper surfa< 

 for articulation with the lower 

 exactly fits the corresponding suri 

 the characteristi i lumbar verl 



articular pro* i 



The dorsal surface of the sa< rui 

 actly correspond in their position I 

 rough, frequently interrupted ridj 

 median ridge, known as the 

 five sacral vertebrae, and is more : 

 rated by the posterii al foramina, the i 



one as the lateral crest. The form< 

 is formed by the fusion of thi 

 cesses on each side retaining 

 first vertebra and the inferior 

 are called the superior arlicula 

 pro. of tin- last luml 



are placed midway between : : 

 downward on each sid< 

 like pnn ess < ailed the 

 and is united by ligaments to a similar pr 



The lateral sural ( 

 and forms a rough ridge which 



The sacrum is travi rs< d tl 

 tinuation oi the spinal canal and 

 part of the sacrum, but rapidly < 

 descends. It terminates externally 

 and is connected with the anh I 

 the intervertebral 



The posterior wall oi tru 



