LYMPHATICS OF RECTUM AND ANUS 



735 



The lymphatics of the transverse colon connect with those of the omentum; those 

 of the descending colon are more scant3^ 



The lymphatics of the rectum and anus. — There are three lymphatic zones 

 of the rectum and anus. (1) An inferior zone, corresponding to the anal integu- 

 ment, in which the capillary networks, both superficial and deep, are extremely 

 abundant, and from which from three to five collecting vessels on either side pass 

 to the inguinal region and end in the medial superficial inguinal nodes. (2) A 



Fig. 576. — The Lymphatic Vessels of the Intestine. (After Mall.) 



( 



middle zone, corresponding with the transition zone of epithelium — that is, with 

 the mucous membrane below the columns of Morgagni. Here the network is 

 coarse, and has its meshes arranged vertically; its ducts drain partly into nodes 

 situated along the inferior and middle hsemorrhoidal arteries, and partly pass to 

 nodes in the meso-rectum, situated along the superior hsemorrhoidal artery and 

 known as the ano-rectal nodes. (3) The superior zone corresponds to the re- 

 mainder of the rectal mucous membrane, and contains a rich network whose 

 coUecting vessels pass to the ano-rectal glands, and thence along the superior 

 hsemorrhoidal arteries to the inferior mesenteric nodes. 



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