Lym phat'ics. Small transparent tubes running through the various tissues, and containing a colorless fluid somewhat thinner than blood, called lymph. This fluid is composed of the leakage from the arteries and of wastes from the tissues, which are being carried to a larger lymph duct to be emptied into one of the larger veins. The lymphatics in the wall of the intestine take up some of the digested food from the cells and pass it on through the lymph glands of the abdomen to the lymph duct which empties into a vein near the heart. Mas ti ca'tion. The process of grinding, or chewing, food in the mouth. Mes'en ter y. The tissue (part of the peritoneum) which is attached to the intestine and, for a few inches, to the spinal column, to hold the coils of the intestine in place. Mu'cous mem'brane. The lining membrane, or tissue, of the entire alimentary canal. It is very complex in structure, has different characteristics in different areas, and contains nerves, blood vessels, lymphatics, and in various parts special structures such as glands. It secretes mucous. It is continuous with the outside skin of the body, as may be seen at the lips. Pan'cre as. The gland that secretes the pancreatic juice; located in the abdominal cavity near the stomach. Pan cre at'ic juice. An alkaline digestive juice poured by the pancreas into the small intestine; especially valuable in the digestion of starches, fats, and proteins. Per i to ne'um. The membrane lining the abdominal cavity and enfolding its organs. Phar'ynx. The passage between the nasal passages and the esophagus: the throat. Py lor'us. (1) The opening from the stomach into the small intestine. (2) The fold of mucous membrane, containing muscle fibres, that helps to regulate the passage of food through the pyloric opening. Sa li'va. The digestive secretion in the mouth, consisting of the secretion of the salivary glands and the secretion of the mucous membrane of the mouth. Stom'ach. The pouch-like enlargement of the alimentary canal, lying in the upper part of the abdominal cavity, and slightly to the left, between the esophagus and the small intestine. III. RELATING TO FOOD AND DRINK Ac'id ([)a]s'[)i]d). A substance (usually sour tasting) that has, among other properties, the power of combining with an alkali in such a way that both substances lose their peculiar characteristics and form a salt. Al'co hol. A colorless liquid formed by the fermentation of starch-sugars or certain other substances, which is highly inflammable and burns without smoke or waste; it is a stimulant and an antiseptic. Al'ka li. A substance that has, among other properties, the power of neutralizing acids and forming salts with them. (See Acid.) Car'bo hy'drates. Plant or animal substances composed of carbon, hydrogen, and oxygen. (Called also starch-sugars.)