GLOSSARY 285 



Inorganic. Matter which has act been elaborated into other compounds 

 by plants or animals. All minerals are inorganic ; also, air and 

 water. 256. 



Insalii-ation. Mixing with saliva. 



Insecticide. A substance which kills insects. 295. 



Internode. In plants, the space between the joints. 205. 



Inter-tillage. Tillage between plants. 85, 85a. 



Intrinsic. Peculiar to, internal, from the inside. The apple has in- 

 trinsic value, that is, it is valuable of itself, to eat, wholly aside 

 from the money it brings. See extrinsic. 



Irrigation. The practice of artificially supplying plants with water, 

 especially on a large scale. 63, 63a. 



Irritable. In plants, responding to external agents, as to wind, sun- 

 shine, heat. 183, 208. 



Larva (plural lamp). The worm-like stage of insects. 



Layer. A part of a plant which is made to take root while still attached 

 to the parent, but which is intended to be severed and to make an 

 independent plant. 229. 



Leaching. Passing through, and going off in drainage waters. 



Leguminous. Belonging to the Leguruinoste or pea family. 110. 



Lichen. A low form of plant-life, allied to algae and fungi. The 

 plant body is usually grayish or dull-colored and dryish. On tree 

 trunks it is usually called "moss." 29. Fig. 3. 



Light soils. Soils which are very loose and open, or which are poor 

 in plant-food. Does not refer to weight. 



Harking out. Making lines or marks on the land to facilitate sowing 

 or planting. 103. 



Medium. A fundamental or underlying substance: soil is a medium 

 for holding water. An agent: a root is a medium for transporting 

 water. 49. 



Microbe. See micro-organism. 



Micro-organism. A microscopic organism. It may be either plant or 

 animal; but the term is commonly restricted to bacteria or mi- 

 crobes or germs, which are now classed with plants. 35a. 



Mineral matter. Earthy matter, iron, potash, lime, phosphorus, etc 



Moldboard. The curved part of the plow which inverts the furrow- 

 slice. 91. 



Mulch. A cover on the soil. 83. 



Nitrate. A compound in which NO 3 is combined with a base. 



Nitrification. The changing of nitrogen into a nitrate. 137. 



Nitrite. A compound in which NO Z is combined with a base. 



