PELVIS. 177 



with the last himbar bone. The apex presents the pos- 

 terior opening of the sacral canal, the posterior articu- 

 lar cavity, the body of the last sacral vertebrae, the 

 vestiges of the articular processes and the posterior 

 notches of that vertebrae. The sacral canal is a part 

 of the rachidian canal, triangular, and is narrowing 

 backwards. 



OssA iNNOMiNATA — Scc postcrior extremity, page 45. 



SYIVDESMOLOOY. 



Sacro-iliac joint. — Arthrodia : Facets of the sides 

 on the base of the sacrum and tlie facets of the internal 

 face of the ilium. Sacro-iliac, superior ilio-sacral, in- 

 ferior ilio-sacral, sacro-sciatic, or ischiatic ligaments. 

 One small synovial capsula. Yery limited sliding 

 motion. 



MYOLOGY. 



See posterior extremity, page 52 and following 

 pages. 



SPLAX( ECOLOGY. 



Rectum. — Posterior portion of the digestive canal 

 and continuation of the floating colon, from which it 

 differs by the absence of ridges, is thicker and has 

 more dilatable walls and is susceptible of large disten- 



