Australian Biological Resources Study
Compiled by A.McCusker
echinate: bearing stiff, stout, prickly hairs. > image <
edaphic: pertaining to the soil.
eglandular: without glands.
elaiosome: an appendage of a seed, usually rich in oil, attractive to fauna (especially ants) and hence an aid to dispersal by such fauna.
elater: in Equisetum, an appendage to the spore.
elliptic: oval in outline, widest at the centre. > image <
emarginate: having a broad, shallow notch at the apex. > image <
embryo: a young plant contained within an archegonium or seed.
embryo-sac: a large, multi-nucleate cell in which an egg nucleus is formed and fertilised, and in which an embryo begins to develop.
emersed: of leaves, flowers, etc., rising above the surface of water in which the plant is rooted.
enation: an epidermal outgrowth.
endemic: having a natural distribution confined to a particular geographical region.
endocarp: the innermost layer of the wall of a fruit; in a drupe, the stony layer surrounding the seed.
endosperm: nutritive tissue in a seed, in angiosperms triploid and formed in the embryo sac after fertilisation, in gymnosperms haploid and derived from the sterile portion of the female gametophyte. cf. perisperm.
entire: having a smooth margin, not dissected or toothed. > image <
entomophilous: pollinated by insects.
epicalyx: a whorl of bracts, just below a flower, looking like a second calyx. > image <
epicarp: the outer layer of the wall of a fruit, i.e. the 'skin'. Also known as the exocarp.
epicormic: of buds, shoots or flowers, borne on the old wood of trees (applied especially to shoots arising from dormant buds after injury or fire).
epicortical: on top of the bark, i.e. outside the bark.
epidermis: the outermost layer of cells of an organ, usually only one cell thick.
epigeal: of germination, having the cotyledon(s) emerging from the seed coat and becoming photosynthetic. cf. hypogeal.
epigynous: of floral parts (especially stamens), attached above the level of insertion of the ovary, and arising from tissue that is fused to the ovary wall. cf. hypogynous, perigynous. > image <
epipetalous: borne on the petals.
epiphyllous: growing on leaves, e.g. the vegetatively derived plantlets of some Crassulaceae; of bryophytes, lichens, fungi, growing upon leaves but not parasitic on them.
epiphyte: a plant growing on, but not parasitic on, another plant (often loosely applied to plants, such as orchids, that grow on vertical rock faces). cf. autotrophic, parasite, saprophyte.
episepalous: of stamens, borne on the sepals.
equilateral: of stamens, with anthers regularly spaced around the style.
equitant: of a leaf, folded in half along the midline so that the adaxial surface disappears from view, and overlapping the edges of a similarly folded leaf on the opposite side of the stem (at least at the base).
eremean: belonging to regions of low, irregular rainfall.
erose: of a margin, finely and irregularly eroded or incised.
eucamptodromous: of leaves, pinnate venation in which the secondary veins do not terminate at the margins but which gradually diminish inside the margin, connected to the superadjacent secondary veins by a series of cross-veins without forming prominent marginal loops. cf. acrodromous, brochidodromous, semicraspedodromous.
eusporangiate: of ferns, having sporangia with walls more than one cell thick. cf. leptosporangiate.
evergreen: bearing green leaves throughout the year. cf. deciduous.
excentric: to one side; off centre.
exine: the outer layer of the wall of a pollen grain or spore.
exocarp (= epicarp): the outer layer or "skin" of the wall of a fruit.
exserted: protruding, e.g. of stamens with respect to a corolla tube.
exstipulate: without stipules.
extrafloral: of nectaries, not within the flower. > image <
extrastaminal: outside the stamens.
extravaginal: of a shoot, arising from an axillary bud which breaks through the sheath of the subtending leaf.
extrorse: of anthers, opening away from the centre of the flower. cf. introrse. > image <