THE DUODENUM. 327 



tubular glands or crypts of Lieberkhiin, like those of the small intes- 

 tine ; and lymphoid nodules (solitary glands) are scattered over the and 

 whole of the large intestine, but are most abundant in the csecum Modules! 

 and vermiform appendix. 



Vessels and nerves. The distribution of the vessels and nerves in Vessels, 

 the wall of the large intestine is the same as in the small. andTym- 



The absorbent vessels, after leaving the gut, join the lymphatic P hatics - 

 glands along the side of the colon. 



RELATIONS OF THE DUODENUM AND PANCREAS. 



Dissection, The student should moderately inflate the stomach Remove 

 and duodenum from the cut extremity of the latter, and remove the l^seeThe 

 loose peritoneum and the fat: while cleaning them, he should lay duodenum, 

 bare the larger vessels and nerves. 



The stomach should be turned upwards, and the pancreas traced and pan- 

 from the spleen on the one side to the duodenum on the other r j!*' 

 (fig. 1 22, p. 329), and the parts behind the stomach cleaned of their 

 fat and peritoneum, care being taken not to injure the vessels and 

 nerves. By pulling forwards the duodenum, the common bile-duct 

 may be found behind, between the intestine and the head of the 

 pancreas ; and some of the pancreas will afterwards be removed, to 

 show its duct entering the duodenum. 



DUODENUM (figs. 121 and 122). The first part of the small intes- Duodenum: 

 tine, or the duodenum, begins at the pyloric end of the stomach, and extent; 

 crossing the spinal column, ends at the duodeno-jejunal flexure on 

 the left side of the second lumbar vertebra. It makes a curve round course and 

 the head of the pancreas, and is placed mainly in the right epigastric 

 and umbilical regions of the abdomen. From its winding course 

 round the pancreas it is divided into four portions (fig. 121, \ 2 , 3 , division, 

 and 4 ). It may be roughly marked on the surface of tJie body by a Surface 

 parallelogram formed by the middle line internally, the right markin s 

 lateral line externally, the transpyloric line above and a line mid- 

 way between the transpyloric and intertubercular lines below ; it 

 being remembered, of course, that the duodenum begins to the right 

 of the middle line. 



The first portion is directed backwards and a little upwards, and First part is 

 is free and movable like the stomach. It measures about two inches ancMs^' 

 in length, and is directed backwards from the pylorus to near the movable, 

 upper end of the right kidney. Above and in front are the liver 

 and gall-bladder ; below is the head of the pancreas ; and behind it 

 are the common bile-duct, the portal vein, and the gastro-duodenal 

 artery with a portion of the head of the pancreas (fig. 123, p. 331). 



The second or descending portion, about three inches in length, second part 

 descends in a groove along the right border of the head of the a 

 pancreas to the level of the third lumbar vertebra, and is fixed 

 almost immovably by the peritoneum and the pancreas. In front of 

 it are the liver and transverse colon ; behind it are the inner border 

 of the kidney, the ureter, and the renal vessels ; and on its inner side 



