THE STOMACH. 905 



which is attached by one edge to the abdominal wall from the lower border of the 

 kidney to the iliac fossa and by the other to the postero-external aspect of the colon ; 

 and the other, mesenterico-parietal, which is in reality the insertion of the mesen- 

 tery into the iliac fossa. In some instances the subcsecal fossa is double. 



3. The Intersigmoid fossa is constant in the foetus and during infancy, but 

 disappears in a certain percentage of cases as age advances. Upon drawing the 

 sigmoid flexure upward, the left surface of the sigmoid mesocolon is exposed, and 

 on it will be seen a funnel-shaped recess of the peritoneum, lying on the external 

 iliac vessels, in the interspace between the Psoas and Iliacus muscles. This is the 

 orifice leading to the fossa intersigmoidea, which lies behind the sigmoid mesocolon, 

 and in front of the parietal peritoneum. The fossa varies in size ; in some instances 

 it is a mere dimple, whereas in others it will admit the Avhole of the index finger. 



Any of these fossae may be the site of a retro-peritoneal hernia. The pericsecal 

 fossae are of especial interest, because hernia of the vermiform appendix frequently 

 takes place into one of them, and may there become strangulated. The presence 

 of these pouches also explains the course which pus has been known to take in 

 cases of perforation of the appendix, where it travels upward behind the ascending 

 colon as far as the Diaphragm. 1 



THE STOMACH. 



The Stomach is the principal organ of digestion. It is the most dilated part of 

 the alimentary canal, and is situated between the termination of the oesophagus and 

 the commencement of the small intestine. Its form is somewhat pyriform with the 

 large end (fundus} directed upward and the small end bent to the right. It is 

 situated in the left hypochondriac and epigastric regions, and is placed, in part, 

 immediately behind the anterior wall of the abdomen and beneath the Diaphragm. 

 Viewing the stomach from in front it appears that the right margin of the oesopha- 

 gus is continued downward as the upper two-thirds of the lesser curvature of the 

 stomach, the remaining third of this border bending sharply backward and to the 

 right, to complete the smaller curvature (Fig. 491). The greater curvature begins at 

 the left border of the termination of the oesoph- 



. , ., / Fundus 



agus in a somewhat acute angle ; it then 

 passes upward and to the left to the under sur- 

 face of the Diaphragm, with which it lies in Cardiac onfice^ 

 contact for some distance, and then sweeps 

 downward with a convexity to the left, and, Lesser curvature 

 continued across the middle line of the body, 

 finally turns upward and backward, to termi- 

 nate at the commencement of the small intes- 

 tine. It will thus be seen that the stomach 

 may be divided into a main or cardiac portion, 

 the lon axis of which is directed downward, pylon 

 with a little inclination forward and to the right, st J r a I ^. 491 -- Diagrammatlc utHne f ' 

 and a smaller or pyloric portion, the long axis 



of which is horizontal with an inclination backward. Of the two openings, the 

 cardiac orifice, by which it communicates with the oesophagus, is situated slightly 

 to the left of the middle line of the body to the right of the fundus, or dilated 

 upper extremity of the stomach, and is directed downward ; the other, the pyloric 

 orifice, by which it communicates with the small intestine, is on a lower plane, close 

 to the right of the mid-line, and looks directly backward. 



The stomach has two surfaces, called anterior and posterior, and two borders, 

 termed the greater and lesser curvatures. 



Surfaces. With regard to the so-called anterior and posterior surfaces ot 

 stomach, it must be borne in mind that these names are not strictly correct, as the 

 anterior surface has a certain amount of inclination upward and the posteno 

 downward. 



1 On the anatomy of these fossae, see the Arrix and Gale Lectures by Moynihan, 1899. 



