248 DIGESTIVE SYSTEiM. 



diaphragm, immediately behind and a little above the small cur- 

 vature of the stomach. Its head is surrounded by the duodenum, 

 with which, and with the stomach and colon, it is chiefly con- 

 nected ; and its body, which is pierced by the vena portse, has 

 one attachment to the spleen, another to the left kidney. 



Of the Hejiection of the Peritoneum. 



In order that the various connexions and relations of the 

 peritoneum may be perfectly understood, it is usual, at this time, 

 to trace (what the Schools call) its rejiectioiis ; by which is 

 meant, to show the way in which it lines the cavity, and after- 

 wards invests the different viscera contained in it. The peri- 

 toneum, though a perfect sac, taken as a whole, is not, as far as 

 regards the cavity of the belly, a circumscribed bag ; at least, it 

 is not in the male, subsequent to the descent of the testicles ; for 

 those organs in their passage carry down a portion of the mem- 

 brane into the scrotum, whereby the cavity of the tunicae va- 

 ginalis (in which the testicle is contained) becomes continuous 

 with that of the abdomen ; and ever afterwards the two have 

 free communication, so that water or air will readily pass from the 

 one to the other : notwithstanding this, however, the integrity of 

 the peritoneum itself remains still unimpaired. In consequence, 

 therefore, of the membrane being continuous at all points, it 

 possessing, the same as a bag without an opening, neither be- 

 ginning nor ending, it imports but little from what part of it 

 description is commenced. We may begin at the inferior part, 

 where it gives a lining to the abdominal muscles, passing from 

 them over the pubes upon the fundus of the bladder, from which 

 it is extended on either side to the parietes of the pelvis, which 

 extensions are called the vesical ligaments. From the fundus it 

 continues round upon the superior surface of the bladder, as far 

 backward as its cervix : at the same time ascending to inclose the 

 rectum and attach it to the sacrum ; thus forming the meso- 

 rectum. From the sacrum it advances upon the lumbar ver- 

 tebrse, which it soon after quits to invest the colon, and after- 

 wards returns to the spine, in this manner forming the meso- 

 colon. It descends from the spine a second time, to invest the 

 whole mass of small intestines (and also the arch of the colon) ; 

 and having done so, returns again, and thus forms the mesentery ; 

 at least one layer of it, the other coming up to meet this from 

 off the surface of the pancreas. Having reached the spine, these 

 two layers unite by adhesion, and become reflected together in a 

 direction downward, and afterwards backward, spreading under 

 the bowels for some short way posteriorly, and then doubling 



