Collier's New Encyclopedia (1921)/Intestines

INTESTINES, the entrails; the portion of the digestive apparatus inferior in position to the stomach. The intestines consist of three coats, an outer one (the peritoneum), an inner or mucous membrane, and an intermediate muscular coat. There are two intestines, the large and the small one. The large intestine extends from the termination of the ileum to the anus. It is about 5 or 6 feet long, or about one-fifth that of the intestinal canal. Its diameter is from 2½ inches to 1½ inches. It is divided into the cæcum, with its vermiform appendix, the colon, and the rectum. The small intestine commences at the pylorus, winds into many convolutions, and terminates in the large intestine. In the adult it is about 20 feet in length. It is arbitrarily divided into three parts—viz., the duodenum, the jejunum, and the ileum. It constitutes four-fifths of the whole intestines, the larger making up the other fifth. They are used to aid in assimilating the food after digestion, and convey forward the excrementiticus matter.