1746 



HUMAN ANATOMY. 



tinuous with them. The two layers join at the bundle of vessels just mentioned, 

 thus forming a fold which is the termination of the lesser omentum on the right, 

 known as the -diiodeno- hepatic omentum (ligamentum hepatoduodenale). The lesser 

 omentum is sometimes described as prolonged across the first part of the duodenum 

 to the transverse colon, fusing with the greater omentum. This is only an acci- 

 dental modification, although a very common one. An accessory fold, the duodeno- 

 cystic ligament^ is prolonged to the right from the front of the lesser omentum, 

 around the cystic duct from the gall-bladder. The hepatic attachment of the lesser 

 omentum is to the transverse fissure of the liver and from its left end to the fissure 

 of the ductus venosus. From the point at which the latter reaches the diaphragm 



the two layers diverge, the 



Fig. 147 1. 



Diagram showing changed relation of visceral peritoneum in consequence 

 of twisting, so that original right and left sides of mesentery of small intes- 

 tine and of part of colon have exchanged places. The detached portion 

 which is twisted is supposed to be attached at a higher level. D, duode- 

 num ; C C ascending and descending colon ; /, small intestine ; A', kidney ; 

 D, C Care being displaced towards posterior wall. 



left one passing to the lower 

 side of the left lobe and the 

 right one to the lobe of 

 Spigelius. The structure 

 of the lesser omentum is 

 dense and fibrous at the 

 right. It is very delicate in 

 the middle, but somewhat 

 thicker at the left end. The 

 fold around the vessels at 

 the free edge (Fig. 1473) 

 forms the anterior border 

 of ihe. foramen of IVins/ozc 

 (foramen epiploicunj), a nar- 

 row part of the peritoneal 

 cavity by which the general 

 cavity communicates with 

 that behind the stomach 

 which has been formed by 

 the rotation of that organ 

 and the inordinate growth 

 of the mesogastrium. The 

 Of the three vessels in 

 the posterior at the point 

 front on the left and the 



foramen is circular, with a diameter of from 2-3 cm. 

 the fold forming its a?iterwr border, the portal vein is 

 of entrance into the liver, with the hepatic artery in 

 hepatic duct in front on the right. The cystic duct is really in an accessory fold. 

 The hepatic artery, which passes along the left side of the duodenum and turns 

 upward, is the vessel that most definitely bounds the foramen in front. The duo- 

 denum lies below the foramen, but its lower border is often formed, not by the 

 gut, but by a fold of serous membrane arising from it. The foramen is bounded 

 behind by the vena cava and above by the caudate lobe of the liver, which is covered 

 by peritoneum. 



The Posterior Mesentery : Part I. — The posterior mesentery arises from the 

 spine, with the aorta between its folds. The first part is the fnesogastrium, in which 

 run the branches of the coeliac axis. It will be remembered that, except at the 

 fundus, this is attached to the greater curvature of the stomach, which was originally 

 the posterior border, but which has turned to the left. The spleen and most of the 

 pancreas are developed in this fold, which grows inordinately. We must trace it both 

 in a horizontal and in a sagittal plane. To understand the horizontal arrangement, 

 it is sufficient to remember that the original mesentery, which ran straight forward 

 from the spine to the stomach, in its subsequent excessive growth describes a loop 

 to the left (Fig. 1470), so that the original left side of the mesentery near its root faces 

 backward, and later, after the bend of the loop, forward, ultimately covering the an- 

 terior wall of the stomach. This fold forms a great pouch behind and below the 

 stomach called the lesser cavity of the peritonetim (bursa omentalis), which, of course, 

 is continuous with the general cavity. The mesothelium of the left side of the mes- 

 entery nearly to the spleen fuses with that of the posterior wall of the abdomen, so 

 that the splenic vessels and the pancreas which are in it come to lie behind the per- 



