THK LARGE IXTESTLXE 



9G9 



A number of closely set acino-tulnilar <;lands, called Brunner^s glanch, iiiav lu' 

 exjtosed l»y dissection in the tirst ])art of the duodenum. 



Blood-supply of the small intestine. — The small intestine receives its blond 

 from the su])(.'ri(»r URSt-ntt-'ric artery, and a branch coming indirectly from the 

 liei)atic, the superior pancreatico-duodenal. The superior mesenteric runs between 

 the layers of the mesentery, and uives off about twelve or fifteen branches, runniujr 

 downwards and to the left (vasa intestini tenuis ), which l)reak uj) and form a series 

 of arches, finally eiicirclinir the intestine as small branches. It also gives off a 

 small branch at the beginning, the inferior pancreatico-duixlenab which, with the 

 superior pancreatico-duodenal, forms an arch, which lies in the concavitv of the 



Fig. 574. — Ve.ssels of the Smalt. Intestine. 



\'eins 



duodenum and supplies it. The blood is returned liy means of the sui>eri(jr 

 mesenteric vein, which with the si)lenic vein forms the portal (tig. 574). 



The lymphatics form a continuous series, which is divided into two sets — viz., 

 tliat of the mucous membrane and that of the muscular coat. The lymph-vessels 

 (if l)oth sets form a copious plexus and end in the mesenteric lacteals (fig. 574). 



The nerves. — The small intestine is sui)i)lied by means of the sujjerior 

 mesenteric jilexus, which is continuous with the lower part of the solar plexus. 

 The brandies follow the blood-vessels, and finally form two plexuses: one (Auer- 

 '-ach's) which lies between the muscular coats; and another (^leissner's) in the 

 submucous coat. 



THE i.ar(;e intestine 



The large intestine is that i)art of the alimentary canal which extends between 

 the ileum and the anus. It is divided into the following ])arts: Ca-cum, ascending, 

 transverse, and descending colon, sigmoid flexure, and rectum. It is so arranged 

 as to surround the small intestine, making a circuit round the alKlominal cavity 

 from right to left (fig. 565). The coscuni lies in the right iliac fossa; thence the 

 colon passes vertically upwards on the right side (ascendini/ colon) until the liver 

 is reached. Here it forms a more or less rectangular bend (hepatic flexure), and 

 then passes transversely acro-ss the belly (transverse colon) below the stomach. It 

 then reaches the splenic area, where it makes a second shariil)end f splenic flexure), 

 and, pa.ssing vertically downwards on the left side (drxirwUnci calon), reaches the 

 left iliac fossa. At this point it forms the looji of the s'ujmoiil flexure, and finally 

 passes through the pelvis as the n^ctum (fig. 577). It is much larger in diameter 

 than the small intestine, and has not the same general convoluted arrangement. 

 Leaving out of consideration the dilated portion of tbi' rectmn it is wid. i- .it tho 



