_Nerved._ Parallel-veined, as the leaves of some trees, 20. _Netted-veined._ With branching veins, forming a network as in the leaves of most of our trees, 20. _Node._ The part of a stem to which a leaf is attached, 18. _Nut._ A hard, unsplitting, usually one-seeded fruit, 27. _Nutlet._ A small nut. _Obcordate._ Heart-shaped, with the stem at the pointed end, 21, 22. _Oblanceolate._ Lanceolate, with the stem at the more pointed end, 21. _Oblong._ Two to four times as long as wide, with the sides somewhat parallel, 20. _Oblique._ Applied to leaves when the sides are unequal, 21. _Obovate._ A reversed ovate, 21. _Obovoid._ A reversed ovoid; an egg form, with stem at the smaller end. _Obscurely._ Not distinctly; usually needing a magnifying-glass to determine. _Obtuse._ Blunt or rounded at tip, 22. _Obvolute_, 34. _Odd-pinnate._ Pinnate, with an end leaflet, 20. _Once-pinnate._ A compound leaf, with but a single series of leaflets along the central stem, 19. _Opposite._ With two leaves on opposite sides of a stem at a node, 18. _Orbicular._ Circular in outline, 20. _Oval._ Broadly elliptical, 20. _Ovary._ The part of the pistil of a flower containing the ovules or future seeds. _Ovate._ Shaped like a section of an egg, with the broader end near the stem, 21. _Overlapping._ One piece spreading over another. _Ovoid._ Ovate or oval in a solid form, like an egg. _Ovules._ The parts within the ovary which may form seeds, 25. _Palmate._ A compound leaf, with the leaflets all starting from the end of the petiole, 19. _Palmately lobed_, 22. _Palmately veined._ With three or more main ribs, or veins of a leaf, starting from the base, 20. _Panicle._ An open, much branched cluster of flowers or fruit, 26. _Pappus._ The down, hairs, or teeth on the end of the fruit in Compositæ, as the thistle-down. _Parallel-veined._ With the veins of the leaf parallel; nerved, 20. _Parted._ Edge of a blade separated three fourths of the distance to the base or midrib, 23. _Pedicel._ The stem of each flower of a cluster, 26. _Peduncle._ The stem of a solitary flower, or the main stem of a cluster, 26. _Pellucid._ Almost or quite transparent. _Peltate._ Applied to a leaf or other part when the stem or stalk is attached within the margin on the side. _Pendent._ Hanging downward, 28. _Pendulous._ Hanging or drooping. _Perfect._ Said of a flower with both stamen and pistil, 25. _Petal._ A leaf of the corolla of a flower, 25. _Petiole._ The stalk or stem of a leaf, 19. _Petiolate._ Said of a leaf which has a stem, 20. _Pinnæ._ The first divisions of a bipinnate or tripinnate leaf. _Pinnate leaf._ A compound leaf with the leaflets arranged along the sides of the stem, 19. _Pinnately lobed_, 22; _Pinnate-veined_, 20. _Pinnatifid._ A leaf deeply notched along the sides in a pinnate manner, 23. _Pistil._ The central essential organ of a flower, 25. _Pistillate._ A flower with pistil but no stamens, 25. _Pith_, 12.