GLOSSARY 431 
Pollin'ium. —A coherent mass of pollen grains in Orchids and Milkweeds, ar¬ 
ranged as to be carried by insects. 
Poly. —A prefix of Greek origin meaning many. 
Polyadelphous. —Applied to stamens which are united by their filaments into 
many sets. 
Polyan'drous. —Having many stamens. 
Polyan'thous. —Many flowered. 
Polyarch. —Said of a radial fibrovascular bundle having many xylem and phloem 
rays. 
Polycar'pellary. —Composed of 3 or more carpels. 
Polycar'pic. —Fruiting successively. 
Polycephal'ic. —Bearing many heads. 
Poly cotyledon.— A plant such as a Conifer which possesses more than 2 cotyle¬ 
dons or seed leaves. 
Polyem'bryony. —Producing more than one embryo within a seed. 
Polyg'amous. —Applied to species in which staminate, pistillate and herm¬ 
aphrodite flowers are borne on the same plant. 
Polyg'onal. —Having several or many angles. 
Polymorphous. —Having several to many different forms. 
Polypet'alous. —Having distinct, disjoined petals. 
Pclyph'yllous. —Many-leaved. 
Polysep'alous. —Having distinct, disjoined sepals. 
Polys'tachous. —Having many spikes. 
Polystem'onous. —Possessing many more stamens than petals. 
Pome. —A fleshy indehiscent fruit, two or more carpelled, with fibrous cartilag¬ 
inous, or stony endocarp, the chief bulk Of which consists of an adherent 
torus. 
Preflora'tion. —See Aestivation. 
Prefolia'tion. —See Vernation. 
Prick'le. —A sharp, rigid outgrowth from the epidermis. 
Primor'dial. —First formed. 
Primor'dial U'tricle. —The outer plasma membrane. The outer layer of proto¬ 
plasm adjacent to the cell wall. 
Procam'bium. —The first formed fibro vascular tissue of any organ before differ¬ 
entiation has taken place into xylem and phloem. 
Procumbent. —Lying flat on the ground. 
Proem'bryo.— The primary stage in the development of Char a consisting of a 
single filament and a long rhizoidal cell. The suspensor in flowering plants. 
Promyce'lium. —A short hyphal growth from resting spores of smuts or rusts 
upon which basidiospores are borne. 
Prosen'chyma. —Tissue composed of elongated, taper-pointed Cells. 
Protan'drous. —A condition of hermaphrodite flowers in which the stamens 
mature before the carpels. 
