THE INTESTINE 



419 



cm.) below the twelfth thoracic vertebra. The cardiac opening is slit-like and is 

 bounded above and to the left by a fold which contains a thickening of the internal 

 ol)lique layer of the muscular coat. The opening into the diverticulum is situated 

 above and a little to the left of the cardia; it is transversely oval, and is bounded 

 (except externally) by a thick fold which contains spirally arranged muscular 

 fibers. The mucous membrane may be divided into four regions. Over a quadri- 

 lateral area around the cardia (about one inch on the right and two or three inches 

 on the left side of the orifice) it is oesophageal in character, and presents a numl^er of 

 folds. A sharp line of demarcation separates this from the rest of the mucous 

 membrane, which is soft and glandular. The second or cardiac gland region is 

 pale gray in color and thin (ca. 0.5 to 1 mm.) ; it extends about to the middle of 

 the stomach. The third or fundus gland region is readily distinguished by its 

 thickness (ca. 3 mm.) and its lirownish-red mottled appearance.^ The fourth or 

 pyloric region is pale, thinner than the preceding, and presents a number of irregular 

 folds. At the pylorus there is a remarkable ridge which projects from the wall of 

 the lesser curvature and diminishes considerably the size of the orifice. It is about 

 an inch and a half (ca. 3 to 4 cm.) long and nearly half an inch (ca. 1 cm.) high. 

 Sometimes it is grooved; in other cases it has tiie form of a rounded eminence 

 attached by a pedicle to the wall. Fibers from the circular muscular coat extend 

 into it. 



Fig. 321. — Liviok of Pig, Soft Specimf.n Skf.tched with I-obes Drawn Apart. 



THE INTESTINE 

 The small intestine is 50 to 65 feet (ca. 15 to 20 m.) long. The mesen- 

 tery of about the first two feet (ca. 60 em.) is two to two and a half inches 

 (ca. 5 to 6 cm.) long; this part may be termed duodenum. The remainder (Jejuno- 

 ileum) has a mesentery about six to eight inches (ca. 15 to 20 cm.) long, which is 

 thick and contains a quantity of fat, and numerous large lymph glands at its root; 

 the root is attached in the sublumbar region behind the stomach and blends here 

 with the mesentery of the large intestine. The small intestine is arranged in close 

 coils and lies mainly on the left side and floor of the abdomen, from the stomach 

 to the pelvis; some coils, however, lie against the right flank. The opening of the 

 bile duct is about one or two inches (ca. 2.5 to 5 cm.) from the pylorus, and that 

 of the pancreatic duct about four or five inches (ca. 10 to 15 cm.) beyond it. Peyer's 



' It will be noted that the fundus gland region does not extend up to the lesser curvature; 

 here the cardiac mucosa joins the pyloric. 



