Pachycauly.   Short, thick, frequently succulent stems, as in

Painted.   Colors disposed in streaks of unequal intensity

Palate.   The raised area in the throat of a sympetalous corolla

Palea.   Inner scale subtending grass floret

Paleaceous.   With small membranous scales, chaffy

Palinactinodromous.   Actinodromous, the primary veins with one or more subsidiary radiations above the primary one

Palmate.   Radiately lobed or divided. Palmately Compound - With leaflets from one point at end of petiole

Palmate-pinnate.   With first order leaflets palmately arranged, second order pinnately arranged

Palmatifid.   Cut palmately

Palmatisect.   Sectioned or divided palmately into distinct segments

Panduriform.   Fiddle-shaped; obovate with sinus or indentation on each side near base and with two small basal lobes

Panicle.   Branched inflorescence with pedicelled flowers

Pannose or Felted.   With matted, feltlike layer of trichomes

Papilionaceous.   With large posterior petal (banner or standard) two lateral petals (wings) and usually two connate lower petals (keel); as in the Fabaceae

Papillose.   Covered with minute tubercles

Pappus.   Bristly or scaly calyx in the Asteraceae

Parallel.   Thecae or anther cells along side of the connective or longitudinal to each other; with veins extending from base to apex, essentially parallel

Parallelodromous.   With two or more primary veins originating beside one another at the blade base and running more or less parallel to the apex where they converge

Paraphyses.   Hairs or hair-like structures in the sorus

Parietal.   With the placentae on the wall or intruding partitions of a unilocular compound ovary

Paripinnately Compound.   Even-pinnately compound, without a terminal leaflet

Parted.   Indentations or incisions cut 1/2-3/4 distance to midrib

Patelliform.   Knee-shaped; disk-shaped

Patent.   Spreading

Pectinate.   Pinnatifid with closely set segments; comb-like

Pedate.   Palmately cut or divided with the lower pair basiscopically exaggerated

Pedicel.   Individual flower stalk

Peduncle.   Main stalk for entire inflorescence

Peg (sterigmata).   Lateral stem projection to which leaf is attached and persistent after leaf dehiscence; ie., abscission layer between peg and leaf; leaf may be sessile; e.g., Picea; or petiolate; e.g. Tsuga, on the peg

Pellucid.   Clear, transparent

Peltate.   Usually having petiole attached near the center on the underside of blade

Peltiform.   Rounded with petiole attached to center of blade or apparently to laminar tissue

Pendent.   Drooping, hanging down; pendulous

Pendulous.   Hanging loosely or freely; pendent

Penni-parallel.   With veins extending from midrib to margins, essentially parallel

Pentacyclic.   Five-whorled

Pentagonal.   Five-angled

Pentamerous.   Whorl with five members

Pentandrous.   With five stamens

Pepo.   A berry with a leathery nonseptate rind derived from an inferior ovary, as in Cucurbita

Perennial, Polycarpic.   Living more than two years; fruiting more than once

Perfect or Bisexual.   With both stamens and carpels or pistils in the flower

Perfoliate.   Having base completely surrounding stem

Perianth.   An aggregation of tepals or combined calyx and corolla

Pericarp.   Fruit wall

Pericarpous.   Around the fruit

Pericladial.   With a sheathing base, as in the Apiaceae

Perigynium.   Sac-like bract subtending the pistillate flower, as in Carex

Perigyny.   The condition in which the sepals, petals, stamens are attached to the floral tube or hypanthium surrounding the ovary with the tube or hypanthium free from the ovary

Peripheral.   On the outer surface or edge

Perisperm.   Food reserve in seed derived from diploid nucellus or integuments

Perispermous.   With food reserve in perisperm, derived from diploid nucellus or integuments

Perispore or Perine.   An outer covering of some fern spores, with different configuration than that of the exospore

Persistent.   Remaining attached; applied to individual parts

Personate.   Two-lipped with the upper arched and the lower protruding into corolla throat

Petal.   A corolla member or segment; a unit of the corolla

Petalantherous.   With a terminal anther and distinctly petaloid filament, as in Saxifraga

Petaliferous.   Most frequently at the base of petals

Petaloid.   Petal-like in shape, texture and/or color

Petalostemonous.   With filaments fused to corolla, anthers free

Petiolar.   May be all over (general) or near apex (acropetiolar) or near base (basipetiolar)

Petiolate.   With a petiole

Petiole.   Leaf stalk

Petiolulate.   With a petiolule

Petiolule.   Leaflet stalk

Petrorhizous.   With roots on rock

Phalaenophily.   Pollinated by moths

Phanerantherous.   With stamens exserted

Phanerocotylar or Epigeous.   With the cotyledons emergent from seed, usually appearing above ground

Photosynthetic.   Blade-like and green

Phyllary.   One of the involucral leaves subtending a capitulum, as in composites

Phyllodial.   Flattened and blade-like

Phyllodium.   Flattened blade-like petiole or midrib

Phyllopodic.   With blade-bearing leaves at base of plant

Phyllotaxis.   Arrangement of leaves, primarily photosynthetic in function

Piliferous.   More than 20:1 l/w, hair-like, flexuous

Pilose.   With soft, shaggy trichomes

Pinna.   A primary division of a fern leaf

Pinnate.   Compound, with the leaflets arranged on both sides of a common axis. Interruptedly Pinnately Compound - With smaller and larger leaflets alternating along the rachis

Pinnate-pinnatifid.   Pinnate with pinnatifid pinnae

Pinnatifid.   Pinnately cut, more than half way to the midvein

Pinnatisect.   Sectioned or divided pinnately into distinct segments

Pinnule.   A secondary division of a fern leaf

Pisiform.   Pea-shaped

Pistil.   One or more fused carpels consisting of stigma, style (if present) and ovary

Pistillate, Carpellate, or Female.   With pistils or carpels only in the flower

Pitcher.   Ventricose to tubular insectivorous leaf, as in Sarracenia

Pith.   Centermost tissue of stem, usually soft

Placenta.   Ovule-bearing region of ovary wall

Planate or Plain.   With lamina flat, without folds or rolls

Platycanthous.   With flat and usually large spines

Plectostele.   A protostele dissected into anastomosing plate-like units

Pleiochasium.   Compound dichasium in which each cymule has three lateral branches

Pleiomerous.   With increase in number of members within whorl

Pleiotaxy.   Increase in number of whorls

Pleomorphic.   Actinomorphic with numbers of parts reduced; e.g., Tripogandra

Pleurogamy.   Pollen tube entrance through side of ovule

Pleurotropous.   Dorsal - Ovule horizontal, micropyle toward ventral bundle, raphe above. Ventral - Ovule horizontal, micropyle toward ventral bundle, raphe below

Plicate or Plaited.   Fluted, longitudinally folded

Pliestesial or Multiperennial.   Monocarpic but living several to many years before flowering, as in Agave

Plumose.   Feather-like

Plumule.   Embryonic leaves in seed derived from epicotyl

Pneumatophorous.   With spongy, aerating roots, usually found in marsh plants

Pollen Grain.   Young male gametophyte. Pollen Sac - Male sporangium

Pollinia.   Grains occurring in uniform coherent masses

Polyad.   Pollen grains in clusters of more than four

Polyandrous.   Many-stamened

Polyanthous.   Having different states in several to many (more than three) different sets of flowers, only one state present in each set

Polycarpellate.   Many-carpellate

Polycephalous.   Many-headed, as in composites

Polycyclic.   Many-whorled

Polydelphous.   With several groups of stamens connate by their filaments

Polygamo-dioecious.   Plants dioecious, but with some perfect flowers on staminate or pistillate plants or both

Polygamo-monoecious.   Plant monoecious, but with some perfect flowers

Polygamous.   Plant with perfect and imperfect flowers

Polyheterophytous.   Having different states in several to many (more than three) different individuals or sets of plants, only one state present in each set

Polymerous.   Whorl with many members

Polymorphic.   Having several to many (more than three) different shapes and/or sizes within the same species

Polyphore.   A receptacle or torus bearing many distinct carpels, as in Rosa

Polystichous.   Leaves or other structures in many rows

Pome (Receptacle and Hypanthium).   A berry-like fruit, adnate to a fleshy receptacle, with cartilaginous endocarp, as in Malus

Poricidal.   Dehiscing through a pore at apex of theca

Porogamy.   Pollen tube entrance through the micropyle

Posterior.   Lobe - The lobe next to axis, away from the subtending bract; adaxial lobe. Posterior Ridges, Lines, Grooves - The lines, grooves, ridges in or on the ventral side, adaxial, within the perianth

Pouch or Sac.   A bag-shaped structure

Precocious.   Developing unusually early

Preformed Shoots.   Normal shoots that develop from winter buds which contain primordia of all leaves that will expand during the season

Prickle.   A sharp pointed outgrowth from the epidermis or cortex of any organ

Prickly.   With prickles

Primary.   From radicle of embryo; tip of main axis

Primocane.   The first year non-flowering stem, as in most blackberries; a turion

Primordium.   Cells in embryo or bud giving rise to roots, leaves or flowers. Protected Primordium - Shoot and/or flower primordia surrounded by scales. Naked Primordium - Shoot and/or flower primordia not surrounded by scales

Proanthesis.   Flowering before normal period, as spring flowers in the fall

Procumbent, Prostrate, or Reclining.   Trailing or lying flat, not rooting at the nodes; humistrate

Proleptic Shoots.   Abnormal late season shoots that develop from the lateral buds immediately beneath the terminal

Promeristem.   Apical growing or meristematic tissue that gives rise to other bud parts

Prop or Stilt.   Adventitious, supporting roots usually arising at lower nodes

Prostrate.   Flat, spreading; growing low along the ground

Protandrous.   With stamens or anthers developing before carpels or stigma

Protantherous.   With leaves appearing before flowers

Prothallus.   Gametophyte of lower vascular plants

Protogynous.   With carpels or stigma maturing before stamens or anthers

Protostele.   Stele having a solid column of vascular tissue with xylem centrally located

Proximal.   Near the point of origin or attachment

Pruinose, Frosted, or Sebiferous.   With a heavy wax coat

Pseudanthium.   Several flowers simulating a simple flower but composed of more than a single axis with subsidiary flowers

Pseudocarp (Receptacle).   An aggregation of achenes embedded in a fleshy receptacle, as in Fragaria

Pseudodrupe (Involucre).   Two-four loculed nut surrounded by a fleshy involucre, as in Juglans

Pseudomonomerous.   Whorl seemingly with one member which is a fusion product of two or more parts

Pseudo-terminal.   Bud appearing apical but is lateral near apex, developing with death or nondevelopment of terminal bud

Psychophily.   Pollinated by butterflies

Pterocauly.   Winged stems

Puberulent.   Minutely pubescent

Pubescent.   Covered with dense or scattered trichomes

Pulverulent.   Covered with fine, powdery wax granules

Pulvinal.   With a swollen base, as in the Fabaceae

Pulvinus.   The swollen base of a petiole or petiolule

Punctate.   Covered with minute impressions or depressions

Pungent.   Acrid; terminating in a rigid sharp point

Purcate.   Forked

Pustulate.   With scattered blisterlike swellings

Pyrene.   Fleshy fruit with each seed surrounded by a bony endocarp, as in Ilex

Pyriform.   Pear-shaped