GLOSSARY 557 



an important fertilizing material and in other forms a valu- 

 able part of the food of men and lower animals. 



Wtrogen-free extract. In plants nutritive compounds contain- 

 ing no nitrogen and consisting chiefly of starch, sugar, etc. 



Noduidue. The scientific name of one group of cut-worms. 



Node. A joint on a stem where a leaf is usually borne. 



Oryza saliva. The scientific name of the rice plant ; the first 

 word is the name of the genus, and the second is the name 

 of the species. 



Oxj-gen. A gas existing in the atmosphere and required in some 

 form by all forms of life. Oxygen also exists in combination 

 with numerous other elements, forming gases, liquids, and 

 sohds. 



Panicle. A branching seed-head, as of oats. 



Papilionacem. The name of the family to which peanuts, 



clovers, and most other cultivated legumes belong. 

 Parasite. An animal i^or vegetable; organism which lives on and 



obtains nourishment from the body of another. 

 Peduncle. In the cotton plant, the stem supporting the square, 



bloom, or boU. 

 Peppergrass. An annual weed of the ^lustard family, seeding 



about the same time as wheat. 

 Phosphatic. Containing a large proportion of phosphorus or 



phosphoric acid. 

 Phosphoric acid. The chemical compound of the elements 



phosphorus and oxygen that makes acid phosphate a 



valuable fertilizer. 

 Piedmont section. The elevated country at the eastern base of 



the Appalachian iMountains. 

 Pine needles. Pine leaves. 

 Pistil. The central portion of a flower at the base of which seed 



maj- develop. 

 Polish wheat. See p. 41. 

 PoUen. The male element in the fertilization of a flower ; usually 



dustlike or in the form of minute particles. 

 Pollen tube. A slender outgrowth from the pollen grain after the 



latter fincls lodgment on a receptive stigma. 

 Polhnation. The act or fact of convej-ing pollen to the receptive 



stigma. 

 Pores. Openings. 

 Pota.sh. The compound of the chemical elements potassium 



and oxygen that makes kainit a valuable fertilizer. 

 Pouland wheat. See \). 40. 

 Protein. Certain compounds rich in nitrogen, found in plants 



and animals. 



