=Perfoliate.= Clasping the stem so completely that the stem seems to pass
through it.

=Perianth.= The calyx and corolla of a flower.

=Perigynium.= A sac-like structure surrounding the achene of a sedge.

=Persistent.= Remaining attached for a considerable time.

=Petal.= One member or segment of the corolla.

=Petiole.= The stalk of a leaf.

=Pinnate.= With several organs or structures attached at the sides of an
axis or stalk; applied chiefly to the arrangement of the principal
veins in a leaf and of leaflets in a compound leaf.

=Pinnatifid.= Deeply pinnately cut or divided.

=Pistil.= The central portion of a flower, consisting of ovary, style, and
stigma; the seed-bearing part of the flower.

=Pistillate.= Bearing pistils.

=Polygamous.= Applied to plants in which some flowers are perfect and
others either staminate or pistillate.

=Pubescent.= Hairy.

=Raceme.= A more or less elongated flower-cluster, bearing pedicelled
flowers along a single axis.

=Racemose.= Arranged in racemes.

=Receptacle.= The end of a peduncle or pedicel upon which the organs of a
flower, or the flowers of a head, are attached.

=Recurved.= Curved back.

=Reflexed.= Abruptly bent back or down.

=Regular.= Uniform in shape or structure. Flowers are generally considered
regular when all the petals are of the same size and shape.

=Retrorse.= Directed backward or downward.

=Revolute.= Rolled backward or under.

=Rootstock.= A horizontal subterranean stem, sending up leaves or stems.

=Rotate.= Wheel-shape; essentially flat and circular.

=Sac-like.= Inflated; sack-like.

=Sagittate.= Shaped like an arrow-head.

=Salver-form.= A corolla having a slender tube abruptly expanded at the
summit into a flat or spreading portion.

=Scape.= A peduncle arising directly from the base of the plant, leafless
or bearing bracts only.

=Segment.= One member or portion of an organ.

=Sepal.= One member or portion of the calyx.

=Serrate.= With sharp teeth at the margin.

=Serrulate.= Finely or minutely serrate.

=Sessile.= Without a stalk, petiole, or pedicel.

=Sheathing.= Inclosing.

=Simple.= In one piece; not compound; usually applied to leaves with a
single blade.

=Sinuate.= Wavy-margined.

=Sinus.= The angle between two lobes or divisions.

=Spadix.= A short fleshy spike.

=Spathe.= A large bract or pair of bracts enclosing a flower-cluster.

=Spat