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DISSECTION OF THE ABDOMEN. 



and extent. 



Divisions. 



Caecum : 

 position ; 

 relations ; 



peritoneum 

 around it. 



Junction of 

 ileum. 



Vermiforn 

 process. 



Surface 

 marking. 



Ascending 

 colon : 



parts 

 around. 



Transverse 

 colon : 



extent and 

 course ; 



splenic 

 flexure 



arch of 

 colon ; 



relations of 

 arch ; 



the'left hypochondriac region ; and it lies in this transverse part of its 

 course in the upper part of the umbilical regions. Finally, it 

 descends, on the left side, through the regions corresponding with 

 those it occupied on the right, and forms a remarkable bend in the 

 pelvis on the left side ; then becoming straight (rectum), it passes 

 through the pelvis to end on the surface of the body. 



It is divided into seven parts, viz., caecum, ascending colon, trans- 

 verse colon, descending colon, iliac colon, pelvic colon, and rectum. 



The caecum is placed in the right iliac fossa, above the outer half 

 of Poupart's ligament, descending below the level of the anterior 

 superior iliac spine in the right lateral line. When empty it may 

 be entirely covered by the convolutions of the small intestine ; but 

 frequently, more or less distended, it rests against the anterior 

 abdominal wall. The caecum is as a rule entirely surrounded by 

 peritoneum, which sometimes forms a small fold behind it ; but 

 occasionally it is closely bound down by the peritoneum being 

 reflected off each side, so as to leave the hinder surface uncovered, 

 and connected to the iliac fascia by areolar tissue. 



This part of the large intestine is joined at its inner and posterior 

 aspect by the termination of the ileum, which marks the division 

 between the caecum and ascending colon. Attached to the inner part of 

 the posterior surface of the caecum is a slender worm-like process the 

 vermiform appendix. This process is usually directed downwards and 

 to the left under cover of the caecum, to which it is connected by a 

 fold of peritoneum. The root of the appendix (where it joins the 

 caecum) is marked on the surface of the body by a point an inch below 

 the centre of a line drawn from the anterior superior iliac spine to 

 the umbilicus. 



The ascending colon reaches from the caecum to the under-surface 

 of the liver, where the intestine makes a bend known as the hepatic 

 flexure. It lies against the iliacus and quadratus lumborum muscles, 

 and in its upper part along the outer border of the kidney. In front 

 and to its inner side are the convolutions of the small intestine. The 

 peritoneum fixes the ascending colon to the wall of the abdomen, 

 and surrounds commonly about two-thirds of its circumference ; 

 but it may encircle the tube and form a fold behind it (ascending 

 meso-colon). 



The transverse colon begins at the hepatic flexure, forming a loop 

 downwards in the right lateral plane as far as the level of the 

 umbilicus, and then passes across to the left and upwards, along 

 the great curvature of the stomach, as far as the spleen. Here 

 a bend, directed mainly backwards, is formed in the lower part of 

 the left hypochondriac region at the junction with the descending 

 colon, sharper than that on the right side, and named the splenic 

 flexure. 



In this course the transverse colon is deeper at each end than in 

 the middle, and thus forms the arch of the colon, which has its 

 convexity directed forwards. Above the arch are placed the liver 

 and gall-bladder, the stomach, and the spleen ; and below, the 



