The =small intestine= is 50 to 65 feet (ca. 15 to 20 m.) long. The
mesentery of about the first two feet (ca. 60 cm.) 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 patches= and
=solitary glands= are numerous and very distinct; the patches are
usually band-like and prominent; the solitary glands form projecting
nodules marked by crypts.
[Illustration: