THE IXTESTIXAL CANAL. 1043 



connected with the rectum. Of course those vessels supply haemorrhoids when 

 the latter are present, but the implication is, they are always present. The 

 term rectal would seem to be correct and the one intended. 



The lymphatics, from mucous and from muscular coats, enter glands anterior 

 to the sacrum. Those near the anus enter inguinal glands. 



The </>>> are from the sacral plexus (cerebro-spinal), and from the inferior 

 mesenteric and hypogastric plexuses (sympathetic). 



In animals the longitudinal muscular fibres have a motor supply from the 

 sacral nerves. 



Relations of the Rectum in Detail. 



FIRST PORTION. 

 Anteriorly : 



^:uall intestines; 



Sigmoid flexure ; 



Posterior surface of bladder in male ; 



Posterior surface of uterus in female. 



Posteriorly : 



Mesorectum ; 



Left Pyriformis muscle ; 



Left sacral plexus ; 



Left internal iliac vessels; 



Anterior surface of first two and a half sacral vertebrae. 



Externally : 



Left ureter ; 



Left internal iliac vessels. 



SECOND PORTION. 

 Anteriorly : 

 (Male) Recto- vesical pouch ; 



^mall intestines; 



Triangular portion of bladder ; 



Vesiculae seminales : 



Vasa deferentia ; 



Under surface of prostate gland. 

 (Female) Posterior wall of vagina ; 



Recto-vaginal pouch ; 



Recto-uterine pouch ; 



Small intestines. 



Posteriorly : 



Lower part of sacrum ; 

 Coccyx ; 



Ano-coccygeal body ; 

 Middle sacral vessels; 

 Origin of Pyriformis muscles. 



THIRD PORTION, OR ANAL CANAL. 

 Anteriorly : 

 (Male) Bulb of urethra ; 



Membranous urethra. 

 (Female) Perineal body. 



Posteriorly : 



Ano-coccvgeal bodv ; 



a / o ** ' 



Coccygei muscles. 



