THE POSTERIOR AORTA. 



619 



of the intestine, where they are disposed in the following manner : The first 

 seven or eight bifurcate, and form arches like those of the arteries supplying the 

 small intestine, differing from them only in being nearer the small curvature of 

 the colon ; the other branches, which are destined for the terminal part of that 



Fig. 366. 



DISTRIBUTION OF THE POSTERIOR OR SMALL MESENTERIC ARTERY. THE SMALL COLON WITH ITS 

 MESENTERY IS SPREAD OUT AND THE SMALL INTESTINE THROWN BACK TO THE RIGHT, UNDER 

 THE DOUBLE COLON. 



1, Trunk of the posterior mesenteric artery ; 2, anterior mesenteric artery ; 3, its anterior 

 fasciculus ; 4, first artery of the small colon, forming part of that fasciculus ; 5, retrograde colic 

 artery ; 6, right fasciculus of the anterior mesenteric; 7, branches of the left fasciculus; 8, renal 

 artery. 9, terminal extremity of the aorta; 10, external iliac artery; 11, circumflex iliac ai'tery; 

 12, internal iliac artery. 



viscus and the rectum, ramify in the intestinal membranes without having 

 previously formed any arches. 



The anterior ramuscule of the first branch anastomoses directly with the 

 artery sent to the small colon by the anterior mesenteric, and from this anasto- 

 mosis results the first colic arterial arch. 



5. Eenal or Emulgent Arteries (Figs. 338, 2 ; 365, 17). 



These are two arteries — one for each kidney — detached laterally, and at a right 

 angle, from the abdominal aorta, near the anterior mesenteric arteiy ; passing 



