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tube, the absorption beginning even in the mouth. What reasons can you give for the absorption of food being many times greater in the small intestine than in the stomach? Through what large tube is the fat carried in passing from the lacteals to the veins? Into what large vein do all the capillaries that take part in absorption empty? (Colored Fig. 5.) What is the provision for storing the sugar so that it will not pass suddenly into the blood after a meal, but may be given to the blood gradually? Food is assimilated, or changed into living matter (proto-*plasm), in the cells. Blood and lymph (except the white corpuscles) are not living matter. (Fig. 100.)

Fig. 100.—The Two Paths of Food Absorption. Thoracic duct (for fats); through the portal vein and liver (for all other foods).

Thought Questions. The Digestive Organs.—1. In which of the digestive organs is only one kind of secretion furnished by glands? 2. In which organ are three kinds of secretions furnished by glands? 3. Which class of food goes through the lymphatics? 4. Which classes of foods go through the liver? 5. Which classes of foods are digested in only one organ? 6. Which classes of foods are digested in two organs? 7. Which division of the food tube is longest? Broadest? Least active? Most active? 8. Soup is absorbed quickly; why does eating it at the beginning of a meal tend to prevent overeating?

Hygienic Habits of Eating.—In hot weather much blood goes to the skin and little to the food tube, and digestion is less vigorous. Hearty eaters suffer from heat in summer because of much fuel, and because the blood is kept away from the skin where it would become cool and then cool the whole body. Some persons believe that the