382 Elementary Principles of Agriculture 



Dependent Plants. Plants that do not have the power of making 



their own food products; i. e., incapable of carbon assimilation. 

 Digestion. The process of converting the insoluble substances of 



foods into soluble materials, preparatory to absorption into 



the blood. 

 Drainage. The process by which surplus water is removed from the 



soil, either by ditches, terraces or tiles. 

 Ecology. The science which treats of the inter-relationships between 



animals and plants, and their environments. The study of the 



modes and conditions of life of plants and animals, a very 



important phase of agricultural science. 

 Element. An original form of matter. An ultimate form of matter 



which can not be further split up by any known means. 

 Emulsion. A more or less permanent and complete mixture of oila 



or fats and water. Fresh milk is an excellent illustration. 

 Endosperm. Reserve food in seeds stored outside of the embryo. 

 Energy. Power; force. Every movement of, or change of body, 



expends energy. The energy of sunlight may be expressed in 



heat, or other form of energy. 

 Ensilage. See Silage. 

 Entomology. Science of insects. 



Erosion. Wearing away. Denudation, as of rocks or soils. 

 Ether Extract. A term used in feed analyses to describe the substances 



removed by ether usually oils. 

 Evolution. The doctrine that present forms of plants and animals 



are descended from previous forms. A theory of the origin of 



forms of living organisms. 



Farming. The practice of raising crops and animals. 

 Farmstead. A farm home or establishment. 

 Fecundation. The union of male and female cells. 

 Fermentation. A chemical change produced by bacteria, yeast, 



etc. Example, souring of milk. The decay of any organic 



substance is due to some form of fermentation. 

 Fertilization. Used in the same sense as fecundation. Also used to 



designate the act of adding fertilizers. 



Fertilizer. A substance added to the soil to improve its productive- 

 ness, as compost. Some fertilizers are known as amendments, 



which see. 

 Fetlock. The long-haired cushion on the back side of a horse's leg, 



just above the hoof. 



