=placentation=, the method of attachment of the ovules, _viz._, =axile= when attached to the axis, but if this axis does not reach the top the placentation is =free central=, and =parietal= when attached to the inner wall of the ovary. =plicate=, folded longitudinally like a closed fan. =plumose=, like a tuft of long feathers, _e.g._, the leaves of a palm. =plumule=, the leaf-bearing part of the embryo. =pod=, a one-celled, two-valved seed vessel. =pollen=, the fertilizing dust contained within the anther. =pollinia= or =pollen-masses=, club-shaped collections of pollen in =Asclepiadaceæ= and =Orchidaceæ=. =polyadelphous=, when the stamens are united into several bundles by junction of filaments. =polyandrous=, with many stamens. =polycarpous= or =polycarpellary=, with many carpels. =polygamous=, bearing male, female and hermaphrodite flowers at the same time on the same plant, but if on distinct plants they are =polygamo- diœcious=. =polypetalous= or =dialypetalous=, when the petals are free. =polysepalous= or =dialysepalous=, when the sepals are free. =præmorse=, as though the end were bitten off. =prickle=, a sharp excrescence from the epidermis of a plant and not from the wood. =procumbent=, of a plant which lies along the ground for the greater part of its length. =prostrate=, when a plant lies down throughout its length. =puberulent=, minutely downy. =pubescent=, downy. =quadrate=, square. =raceme=, an inflorescence in which stalked flowers are inserted along a central axis. =rachilla= and =rachis=, see =rhachilla= and =rhachis=. =radical=, springing from the root. =radicle=, the embryo root. =ray florets=, the outer florets, in the capitulum of certain =Compositæ=. =rays= of an umbel, the pedicels bearing the flowers or secondary umbels. =receptacle=, the short, flat, convex or conical axis on which the flowers of a head are seated, as in =Compositæ=; also the extremity of the flower-stalk above the calyx (also called =torus=) on which the corolla, stamens and pistil are inserted. =reclinate=, bent downwards. =recurved=, bent back. =reduplicate=, folded back. =reflexed=, bent back abruptly. =regular=, applied to a flower means that all parts of the floral whorls are equal among themselves. =reniform=, kidney-shaped. =reticulated=, net-like. =retrorse=, turned backwards. =retuse=, very blunt and slightly indented. =revolute=, rolled back, in case of a leaf towards the underside. =rhachilla=, a secondary axis in the flowers of =Sedges= and =Grasses=. =rhachis=, the stalk of a compound leaf bearing the leaflets; also the portion of the axis of an inflorescence from the lowest ramification upwards. =rhomboidal=, applied to leaves or leaflets means more or less 4-angled but not square. =rostellate=, with a small beak. =rostrate=, beaked. =rosulate=, rosette-shaped. =rotate=, wheel-shaped; of a corolla when the petals or lobes are spread out horizontally from the base. =rufous=, foxy-red.