2. That this food supply must be oxidized before energy is released. 3. That in cases where the food is not stored at the point where it is to be oxidized the food must be digested so that it may be transported from one part to another in the same plant. The life processes of plants and animals, so far, may be considered as alike; they both feed, breathe (oxidize their food), do work, and grow. REFERENCE BOOKS ELEMENTARY Hunter, _Laboratory Problems in Civic Biology_. American Book Company. Andrews, _A Practical Course in Botany_, pages 1-21. American Book Company. Atkinson, _First Studies of Plant Life_, Chap. XXX. Ginn and Company. Bailey, _Botany_, Chaps. XX, XXX. The Macmillan Company. Beal, _Seed Dispersal_. Ginn and Company. Bergen and Davis, _Principles of Botany_, Chaps. XX, XXX. Ginn and Company. Coulter, _Plant Life and Plant Uses_. American Book Company. Dana, _Plants and their Children_. American Book Company. Mayne and Hatch, _High School Agriculture_. American Book Company. Lubbock, _Flowers, Fruits, and Leaves_. The Macmillan Company. Newell, _Reader in Botany_, pages 24-49. Ginn and Company. Sharpe, _A Laboratory Manual in Biology_, pages 55-65. American Book Company. ADVANCED Bailey, _The Evolution of our Native Fruits_. The Macmillan Company. Bailey, _Plant Breeding_. The Macmillan Company. Coulter, Barnes, and Cowles, _A Textbook of Botany_, Vol. I. American Book Company. De Candolle, _Origin of Cultivated Plants_. D. Appleton and Company. Duggar, _Plant Physiology_. The Macmillan Company. Farmers' Bulletins, Nos. 78, 86, 225, 344. U. S. Department of Agriculture. Hodge, _Nature Study and Life_, Chaps. X, XX. Ginn and Company. Kerner (translated by Oliver), _Natural History of Plants_. Henry Holt and Company, 4 vols. Vol. II, Part 2. Sargent, _Corn Plants_. Houghton, Mifflin, and Company. VI. THE ORGANS OF NUTRITION IN PLANTS--THE SOIL AND ITS RELATION TO THE ROOTS _Problem.--What a plant takes from the soil and how it gets it._ _(a) What determines the direction of growth of roots?_ _(b) How is the root built?_ _(d) What is in the soil that a root might take out?_ _(e) Why is nitrogen necessary, and how is it obtained?_ LABORATORY SUGGESTIONS