GLOSSARY 731 
Prin’NULE.—A secondary pinna. 
P1’strorM.—Pea-shaped, 
Pis't1..—The central female organ of a flower consisting of one or more united 
carpels. 
Pis’r1LLATE.—Applied to flowers that possess one or more carpels but no fertile 
stamens. 
Prru (Medulla).—The core of soft parenchymatous tissue at the center of stems or 
roots. 
PLAcEN’TA.—The nourishing tissue which connects the ovules with the wall of 
the ovary. 
PLACENTA’TION.—The arrangement of the placenta within the ovary or the pericarp. 
PLAsMA Mem’BRANE (Outer Plasma Membrane).—See Ectoplasm. 
PLAsMo’D1uM.—A multinucleated, naked mass of protoplasm having amoeboid 
movement. The vegetative body of a Slime Mold. 
PLAsMOL’ysis.—A contraction of the protoplasm of a cell due to the extraction of 
contained water under the arises of reagents of greater density than the 
protoplasmic sap. 
PLAs’tTrps.—Dense, porous protoplasmic bodies of various shapes scattered about in 
the cytoplasm. : 
PLe’rRomME.—A meristem found in the apical regions of plant axes which gives rise 
to fibrovascular tissue. 
Pui'cAte.—Folded like a fan. 
Piumose’,—Feathery. 
Piu’mMuLe.—The rudimentary bud between the cotyledons. 
Piurioc’uLAR.—Having more than one chamber or cell. 
Po’LAR Bopy.—A portion of a gamete budded off before fertilization. 
Pot’LeEn.—The fertilizing dust composed of cells produced in the anthers of flowers. 
Potten Gratin (Microspore).—A cell developed within the anther-sac and which 
carries the male fertilizing element. 
PotuinaA’t10on.—The transfer of pollen from anther to stigma and subsequent 
germination thereon. 
Poutin’tum.—A coherent mass of pollen grains in Orchids and Milkweeds, arranged 
as to be carried by insects. 
Po.y.—A prefix of Greek origin meaning many. 
Potyape.’pHous.—Applied to stamens which are united by their filaments into 
many sets. 
PoLtyAn’pRous.—Having many stamens. 
PoLyAn’THOUs.——Many flowered. 
PoLyarcu’.—Said of a radial vascular bundle having many — and phloem 
rays. 
PoLycAR’PELLARY.—Composed of 3 or more carpels. 
Potycar’pic.—Fruiting successively. 
PoLycrPHAL’1c.—Bearing many heads. 
Po.ycoryLep’on.—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. 
Po.ya’Amous.—Applied to species in which staminate, pistillate and hermaphrodite 
flowers are borne on the same plant. 
Po.yc’oNnAL.—Having several or many angles. 
