ANGEIOLOGY. 91 



to the upper surface of the pylorus, and the gastro-duodenalis^ which in turn 

 yields inferior pyloric branches, the 'pancreatico-dv.odenalis, and the gastro- 

 epiploica dextra ; the first to the lower part of the pylorus, the second to the 

 duodenum and pancreas, and the third to the great omentum and stomach. 

 The rigid and left hepatic arteries then separate and plunge into the substance 

 of the liver, accompanied by branches of the vena porta ; the right hepatic 

 is the larger, and before entering the gland gives off the cystic artery to the 

 gall bladder. 



c. The splenic artery. This is the longest branch of the coeliac axis ; it 

 passes backwards and to the left side along the upper edge of the pancreas, 

 to which it sends several branches. Near the spleen it gives off the gastro- 

 epiploica sinistra. It next sends off the vasa hrevia, small branches which 

 go to the great end of the stomach. The splenic artery then divides into 

 several branches, which enter into the spleen. 



PI. 134, fig. 4, the abdominal aorta: \ diaphragm; \ kidney; ", supra- 

 renal capsule ; ', aorta; ■*' ^' ", visceral arteries cutoff; ', supa-renal artery; 

 ', renal arter}»- ; °, internal spermatic ; '°, a lumbar artery ; ", phrenic artery. 

 Fig. 3, coeliac artery: ', liver; '^, gall bladder; ', round ligament of the 

 liver, formerly the umbilical vein ; \ stomach ; '% duodenum ; ", the spleen ; 

 ', pancreas; ^, trunk of the coeliac artery; ^' ", gastric artery; '", hepatic 

 artery; '*, gastro-epiploica dextra; ", cystic artery; ", splenic; '°, outline 

 of the course of the splenic artery behind the stomach ; '", gastro-epiploica 

 sinistra; ", vasa brevia. 



3. Superior Mesenteric Artery. This arises below the coeliac ; de- 

 scends obliquely forwards and to the left behind the pancreas and over the 

 duodenum ; it then passes between the layers of the mesentery and takes 

 an arched course towards the right iliac fossa : from its concave side arise 

 three branches, the ileo-colic, the right colic, and the middle colic. These 

 branches proceed between the laminee of the mesocolon to the large intes- 

 tine ; each dividing into two branches which unite with those on either 

 side and form arches, from whose convexities other subdividing branches 

 again arise and unite as before. These divisions and subsequent inoscula- 

 tions occur several times before reaching the intestine, near which each 

 branch divides into two, which proceed in a direct course, one on the 

 anterior, the other on the posterior surface of the intestine, and are distri- 

 buted principally to the submucous tissue. 



PI. 1S4:, fig. 4^, origin of the superior mesenteric. 



PI. 135, fig. 11, distribution of the superior mesenteric: \ folds of the 

 small intestines : *, coecum ; \ its vermiform appendage ; \ ascending colon ; 

 ', transverse colon ; ", superior mesenteric artery with branches going off 

 to the small intestines, forming numerous inosculations ; ', right colic artery; 

 ', middle colic. 



4. The Inferior Mesenteric Artery arises about two inches below 

 the preceding; it descends towards the left iliac fossa and divides into three 

 branches, the left colic, sigmoid, and superior hemorrhoidal. 



T'he left colic artery ascends in the left mesocolon, anastomoses with the 

 middle colic branch of the superior mesenteric, and supplies the left part 



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