RECTUM. 



505 



with it, are the branches of the left internal artery, and the left ureter. 

 In some bodies this part of the intestine is much curved to the right 

 side. 1 



The middle piece lies beneatli the bladder, and reaches to the tip of the 

 coccyx: it is about three inches in length, and is covered by peritoneum 

 on the front and sides above, but only in front below. Resting on it is 

 the triangular part of the bladder, with the back of the prostate and the 

 vesiculae seminales and vasa deferentia; and beneath it are the sacrum and 

 coccyx. On each side is the coccygeus muscle. 



Fig. 174. 



SIDE VIEW OF THE DISSECTED MALI-: PELVIS. 



a. Urinary bladder. g. Vesicula seminalis. 



6. Prostate. h. Ureter. 



c. Membranous part of the urethra. i. Recto-vesical fascia. 



d. Spongy part of the urethra. ft. Rectum. 



e Crus penis, detached. I. Levator ani, cut. 

 /. Vas deferens. 



The lower part is about an inch and a half long, and is curved from the 

 tip of the coccyx to the anus: at first it is dilated, but at the anus it is 

 contracted. This end of the intestine is without peritoneal covering, and 

 is supported by the lower part of the triangular ligament of the urethra, 

 and by the levatores ani muscles. 



Above the extremity of the rectum (in this position of the body) are the 

 fore part of the prostate, the membranous part of the urethra, and the 



' It is not uncommon to see the rectum on the right side of the sacrum. In the 

 dissecting-room of University College in one winter (1854-1855), I saw three ex- 

 amples of the rectum in that situation. In two bodies the lower end of the Ipft 

 colon crossed tiie spine at the top of the sacrum, and the rectum descended 

 through the pelvis, on the right of the middle line, to the end of the coccyx. In 

 the third the large intestine crossed the spine twice, once at top of the sacrum, 

 and again about the middle of that bone. 



