VI GLOSSARY 



nectary. A cup, sac, or place in the flower in which nectar (or 



" honey ") is borne. 

 osmosis. The passing or diffusion of liquids or gases through mem- 

 branes. 

 ovary. The lower enlarged part of the pistil, containing the ovules or 



forming seeds. 

 ovule. The young or forming seed. 

 palmate. Palm-like ; said of venation that arises from the base of the 



leaf (top of petiole), or of leaflets similarly arranged. 

 panicle. A branching raceme. The lower or outer flowers open first ; 



but the word is often used loosely. 

 pappus. The hair, plumes, bristles, or scales on the top of a dry fruit, 



particularly of a fruit (or " seed ") of the Compositae or sunflower 



family. 

 parasite. A plant or animal that lives on a living host (as on a plant 



or an animal), taking its food from the host. See saprophyte, 

 parenchyma. The general underlying tissue, from which other tissue 



arises. (Word not derived itom parent.) 

 pedicel. Stem of a single flower in a cluster. 

 peduncle. A flower stem, supporting a solitary flower or a cluster of 



flo~wers. 

 perennial. A plant that lives more than two years, as most grasses, 



docks, alfalfa, asparagus, and all trees and shrubs. 

 perfect flowers bear both stamens and pistils. 

 pericarp. A ripened ovary, without counting attached parts. 

 personate. Masked ; that is, so formed as to suggest a masked face, 



in labiate corollas with a large lower lip. 

 petal. One of the parts or leaves of the corolla. 

 petiole. Stem or stalk of a leaf. 

 petiolule. Stem of a leaflet. 

 phenogam {phanogam, phanerogam) . A seed-bearing plant ; that is, 



one of the seed-bearing or flowering group of plants. 

 phloem. Bark or soft bast tissue. 

 photosynthesis. The process whereby the carbon dioxid of the air is 



appropriated in the formation of material for plant growth. 

 phyllotaxy. Mode of arrangement of leaves or flowers on the plant or 



stem. 

 pinnate. Feather-like ; said of leaves in which the veins strike off 



from a continuing midrib, or in which the leaflets are arranged in 



a similar order. 

 pistil. The innermost member in the flower, bearing the forming seeds. 

 pistillate. Of pistils only; a flower that contains pistils and no 



stamens, or a plant that bears only pistils. 



