Deciduous.   Persistent for one growing season


Declinate.   Directed or curved downward


Decompound.   A general term for leaflets in two or more orders - bi-, tri-etc - pinnately, palmately, or ternately compound


Decumbent.   Reclining or lying on the ground with the tips ascending


Decurrent.   Elongate, extending downward


Decussate.   Opposite leaves at right angle to preceding pair


Deflexed.   Bent abruptly downward


Dehiscent.   Opening regularly by valves, slits, etc., as a capsule or anther


Deliquescent.   Softening and wasting away


Dentate.   Margins with rounded or sharp, coarse teeth that point outwards at right angles to midrib or midvein, cut 1/16 to 1/8 distance to midrib or midvein


Denticidal Capsule.   One that dehisces apically, leaving a ring of teeth, as in Cerastium


Denticulate.   Diminutive of dentate, cut to 1/16 distance to midrib or midvein


Depauperate.   Small and usually poorly developed


Depressed.   Pressed closely to axis downward with angle of divergence of 166-180°


Descending.   Directed downward with an angle of divergence of 136-165°


Determinate.   Growth of plant parts, the size of which is limited by cessation of meristematic activity during the year


Dextrorse.   Rising helically from right to left, a characteristic of twining stems


Diadelphous.   With two groups of stamens connate by their filaments


Diandrous.   With two stamens per flower


Diaphanous.   Translucent


Dichasium.   Cymose inflorescence in which each axis produces a pair of lateral axes


Dichlamydeous.   With perianth composed of distinct calyx and corolla


Dichogamous.   With maturation of stamens or anther and carpels or stigma at different times


Dichotomous.   With branches forking into two more or less equal parts


Diclesium (Calyx).   Achene or nut surrounded by a persistent calyx, as in Mirabalis


Diclinous.   Plant with imperfect flowers; stamens and carpels in separate flowers either monoecious or dioecious


Dicotyledonous.   With two cotyledons


Dictyostele.   A dissected solenostele with each individual bundle a meristele


Dicyclic.   Two-whorled


Didymous.   With stamens in two equal pairs


Didynamous.   With stamens in two unequal pairs


Diffuse.   Spread over a wide surface


Digestive Glands.   Enzyme-secreting glands found mostly on leaves of carnivorous and insectivorous plants


Dilated.   Widened; expanded


Dimerous.   Whorl with two members


Dimidiate.   Divided into unequal halves


Dimorphic.   Having two different sizes and/or shapes within the same species


Dioecious.   Plant with all flowers imperfect, but staminate and pistillate on separate plants


Diplecolobal.   With incumbent cotyledons folded two or more times


Diplostemonous.   With stamens in two whorls, outer opposite the sepals, inner opposite petals


Diplotegium.   A pyxis derived from an inferior ovary


Dipterous.   Two-winged


Disc.   A discoid structure developed from receptacle at base of ovary or from stamens around the ovary


Discoid.   Orbicular with convex faces


Discoidal.   A single large spot of color in the center of another


Discontinuous.   Basal and lateral, basal and terminal, or lateral and terminal; not continuous


Dissected.   Irregularly cut into numerous segments


Distal.   Away from the point of origin or attachment


Distichous.   Leaves 2-ranked, in one plane


Distinct.   With like parts or organs unjoined and separate from one another


Diurnal.   Opening during the day


Divergent, Patent, or Divaricate.   More or less horizontally spreading with angle of divergence of 15° or less up or down from the horizontal


Divided.   Cut 3/4 to almost entire distance to middle of structure


Dolabriform.   Axe-shaped


Dorsal.   Pertaining to the surface most distant from the axis; back of an outer face of organ; lower side of leaf; abaxial. Dorsal Side - Back or abaxial side, or the lower side of a perianth part


Dorsifixed.   Anther attached dorsally and medially to apex of filament


Dorsilaminar.   On dorsal side of blade


Dorsiventral.   Planate and having distinct dorsal and ventral surfaces, the two usually different


Dotted.   The color disposed in very small round spots


Downy.   Covered with short, weak, soft trichomes


Drupe.   A fleshy fruit with a stony endocarp, as in Prunus


Drupecetum.   An aggregation of drupelets, as in Rubus


Drupelet.   A small drupe, as in Rubus


Dwarf.   Very small. Dwarf Shoots or Spurs - Shoots that develop from preformed buds which have very short internodal lengths or intervals


Dyad.   Pollen grains occurring in clusters of two


Eccentric.   Off-center style


Echinate.   Covered with spines


Ectocarp or Exocarp.   Outermost layer of pericarp


Edged.   One color is surrounded by a very narrow rim of another


Elaminate.   Without blade


Elater.   One of four elongate appendages on the spores, as in Equisetum


Elliptic.   With widest axis at midpoint of structure and with margins symmetrically curved


Emarginate.   Lobe rounded; sinus depth 1/16-1/8 distance to midpoint of blade; margins straight or convex


Embryo.   Young sporophyte consisting of epicotyl, hypocotyl, radicle, and one or more cotyledons. Embryo Sac - Female gametophyte. Linear Embryo - Axial embryo several times longer than broad, straight, curved or coiled; cotyledons not expanded; endosperm present or absent


Emergent.   With part(s) of plant aerial and part(s) submersed; rising out of the water above the surface


Emersifolious.   With emergent leaves


Endocarp.   Innermost differentiated layer of pericarp


Endosperm.   Food reserve tissue in seed derived from fertilized polar nuclei; or food reserve derived from megametophyte in gymnosperms


Endospermous or Albuminous.   With food reserve in endosperm or albumen, derived from fertilized polar nuclei


Entire.   Without indentations or incisions on maigins; smooth


Entomophily.   Pollinated by insects


Eophyll.   Term applied to first few leaves with green, expanded lamina developed by seedlings; transitional type leaves developed before formation of adult leaves


Epetiolate.   Without petiole, leaf sessile


Epetiolulate.   Without petiolule, leaflet sessile


Ephemeral.   Germinating, growing, flowering and fruiting in a short period, as most desert herbs


Epicalyx.   Group of leaves resembling sepals below the true calyx


Epicalyx or Calycle.   A whorl of bracts below but resembling a true calyx


Epicormic Shoots or Water Sprouts.   Shoots that develop from dormant lateral buds on the trunk which have very long and frequently variable internodal lengths or intervals


Epicotyl.   Apical end of embryo axis that gives rise to shoot system


Epigyny.   The condition in which the sepals, petals, stamens are attached to the floral tube above the ovary with the ovary adnate to the tube or hypanthium


Epihyperigyny.   The condition in which the sepals, petals, stamens are attached to the floral tube or hypanthium surrounding the ovary; a combination perigyny and partly inferior ovary


Epihypogyny.   The condition in which the sepals, petals, stamens are attached about half-way from the base of the ovary to the partly adnate hypanthium tube; half-inferior insertion of parts


Epimatium.   Fleshy covering of the seed and more or less fused with the integument; arising from the chalazal end of the ovule like an additional integument; e.g., Podocarpus


Epiperigyny.   The condition in which the sepals, petals, stamens are attached to the floral or hypanthium cup above the ovary with the lower part of the hypanthium completely adnate to the ovary


Epipetalous.   With stamens attached to or inserted upon petals or corolla


Epipetiolar.   With branches arising from buds on the petiole


Epipetric.   Upon rock


Epiphyllous.   From a phylloclad or peculiar bract, as in Tilia


Epiphytic.   Upon another plant


Epirhizous.   With roots upon another plant


Episepalous.   With stamens attached or inserted upon sepals or calyx


Epitropous .  Dorsal - Ovule pendulous or hanging, micropyle above, raphe dorsal (away from ventral bundle). Ventral - Ovule pendulous or hanging, micropyle above, raphe ventral (toward ventral bundle)


Equilateral.   With halves or sides equal in shape and size


Equinoctial.   Having flowers which expand and close regularly at particular hours of the day


Equitant.   Leaves 2-ranked with overlapping bases, usually sharply folded along midrib


Eramous.   With unbranched stems


Erect.   Upright


Erose.   Irregularly, shallowly toothed and/or lobed margins; appearing gnawed


Essential Organs.   The androecium and gynoecium


Ethereal Oil Producing Glands.   Mostly aromatic compound producing glands found on various parts of the plant, without definitely known functions


Eucamptodromous.   With a single primary vein, the secondary veins curved upward and gradually iminishing distally within the margin and interconnected by a series of cross-veins without forming conspicuous marginal loops


Eusporangiate.   Having the sporangium develop from a great amount of leaf tissue as opposed to only one or a few cells


Eustele.   A dissected siphonostele with phloem only to the outside of the xylem


Evanescent.   Passing away, disappearing early


Evergreen.   Persistent two or more growing seasons


Evident.   Clearly visible macroscopically


Excentric.   One-sided; off-center


Excurrent.   Running out, as the nerve of a leaf projecting beyond the margin


Exospore or Exine.   Outer spore wall layer


Exsserted.   Projecting out of, beyond


Exstipellate.   Without stipels


Exstipulate.   Without stipules