_Ocreate_, furnished with _Ocreæ_ (boots), or stipules in the form of sheaths, 67. _Octo-_, Latin for eight, enters into the composition of _Octagynous_, with eight pistils or styles; _Octamerous_, its parts in eights; _Octandrous_, with eight stamens, &c. _Oculate_, with eye-shaped marking. _Officinal_, used in medicine, therefore kept in the shops. _Offset_, short branches next the ground which take root, 40. _Oides_, termination, from the Greek, to denote likeness; so _Dianthoides_, Pink-like. _Oleraceous_, esculent, as a pot-herb. _Oligos_, Greek for few; thus _Oliganthous_, few-flowered, &c. _Olivaceous_, olive-green. _Oophoridium_, a name for spore-case containing macrospores. _Opaque_, applied to a surface, means dull, not shining. _Operculate_, furnished with a lid (_Operculum_), as the spore-case of Mosses, 163. _Opposite_, said of leaves and branches when on opposite sides of the stem from each other (i. e. in pairs), 29, 68. Stamens are opposite the petals, &c., when they stand before them. _Oppositifolius_, situated opposite a leaf. _Orbicular_, _Orbiculate_, circular in outline, or nearly so, 52. _Order_, group below class, 178. _Ordinal names_, 180. _Organ_, any member of the plant, as a leaf, a stamen, &c. _Organography_, study of organs, 9. _Organogenesis_, that of the development of organs. _Orgyalis_, of the height of a man. _Orthos_, Greek for straight; thus, _Orthocarpous_, with straight fruit; _Orthostichous_, straight-ranked. _Orthotropous_ (ovule or seed), 111. _Osseous_, of a bony texture. _Outgrowths_, growths from the surface of a leaf, petal, &c. _Oval_, broadly elliptical, 52. _Ovary_, that part of the pistil containing the ovules or future seeds, 14, 80, 105. _Ovate_, shaped like an egg, with the broader end downwards; or, in plain surfaces, such as leaves, like the section of an egg lengthwise, 52. _Ovoid_, ovate or oval in a solid form. _Ovule_, the body which is destined to become a seed, 14, 80, 105, 110. _Ovuliferous_, ovule-bearing. _Palate_, a projection of the lower lip of a labiate corolla into the throat, as in Snapdragon, &c. _Palea_ (plural _paleæ_), chaff; the inner husks of Grasses; the chaff or bracts on the receptacle of many Compositæ, as Coreopsis, and Sunflower. _Paleaceous_, furnished with chaff, or chaffy in texture. _Paleolate_, having _Paleolæ_ or paleæ of a second order, or narrow paleæ. _Palet_, English term for palea. _Palmate_, when leaflets or the divisions of a leaf all spread from the apex of the petiole, like the hand with the outspread fingers, 57, 58. _Palmately_ (veined, lobed, &c.), in a palmate manner, 51, 56. _Palmatifid_, _-lobed_, _-sect_, palmately cleft, or lobed, or divided. _Paludose_, inhabiting marshes. _Palustrine_, same. _Panduriform_, or _Pandurate_, fiddle-shaped (which see). _Panicle_, an open and branched cluster, 81. _Panicled_, _Paniculate_, arranged in panicles, or like a panicle.