Glossary of Botanical Terms:

abaxial: facing away from axis or stem, such as the lower surface of a leaf. cf. adaxial.

abortive: imperfectly developed; infertile.

abscission: the normal shedding from a plant of an organ that is mature or aged, e.g. a ripe fruit, an old leaf. adj. abscissile.

acaulescent: without a trunk.

accessory fruit: a fruit, or group of fruits derived from one flower, in which the conspicuous, fleshy portion develops from the receptacle and is shed with the true fruit(s) attached, e.g. apple, rose hip and strawberry. Fig. 18 C, V & W.

accrescent: expanding after flowering, increasing in size with age, e.g. the calyx expanding around the base of a fruit.

achene: a dry indehiscent 1-seeded fruit, from an either superior or inferior ovary of 1 carpel, with the seed not fused to the fruit wall; e.g. as in Ranunculaceae (from a superior ovary) and Asteraceae (from an inferior ovary and usually topped by the pappus and sometimes called a cypsela). Fig. 18 Q, R & W.

acicular: needle-shaped.

actinomorphic: of a flower with the parts in each whorl particularly sepals, petals and stamens not differing in shape, size or placement. The flower therefore can be bisected symmetrically in several planes. cf. zygomorphic.

aculeate: prickly.

acumen: a long, tapering point.

acuminate: gradually tapering to a point. Fig. 6 C.

acute: pointed, having a short sharp apex, the converging edges forming an angle of less than 900. Fig. 6 D. cf. obtuse.

adaxial: facing towards the axis or stem. cf. abaxial.

adhesion: where two dissimilar parts or organs stick together but without organic fusion. adj. adherent. cf. cohesion.

adnate: (1) fusion of unlike parts, e.g. stamens fused to the corolla, cf. connate; (2) of an anther which has a broad point of attachment by which it is rigidly held at the apex of the filament, as in some eucalypts (family Myrtaceae). cf. versatile.

adventitious: term describing any organ arising in an abnormal position, e.g. roots arising from the shoot system.

adventive: introduced accidentally, as most exotic weeds are; often used of introductions that are not fully naturalized.

aerial root: an adventitious root growing from the stem above ground level.

aestivation: arrangement of the sepals and petals or their lobes in the unopened bud. Fig. 11. cf. vernation.

aff.: with affinities to.

agglutinated: stuck together, formed into clumps of cells, e.g. of pollen grains.

aggregate fruit: cluster of fruits derived from a single flower in which the carpels are free, or almost so, from each other. e.g. as in many Ranunculaceae, Annonaceae, Rosaceae. Fig. 18 V–X. cf. multiple fruit.

albumen: see endosperm.

allopatric: of two or more taxa, having different ranges of distribution, not overlapping. cf. sympatric.

alternate: (1) of leaves or flowers, inserted singly at different levels along the branches (commonly used to include spiral arrangement), Fig. 2 A & B; (2) between, as in ‘stamens alternate with the petals’.

amphicarpous: with two kinds of fruits; differing in position, character or time of ripening.

amphistomatic: leaves with stomates on both upper and lower surfaces. cf. hypostomatic.

amphitropous: of an ovule with the body bent or curved on both sides so that the micropyle is near the funicle; the embryo sac is curved. Fig. 21 E. cf. anatropous, campylotropous, hemitropous, orthotropous.

amplexicaul (perfoliate): a term used of a leaf base, where it clasps the stem. Fig. 4 F.

ampulliform: swollen at base like flask.

anastomosing: fusing to form a network, as in the veins of a leaf.

anatropous: of an ovule, with the body completely inverted so that the micropyle area is adjacent to the funicle, the embryo sac is more or less straight. Fig. 21 F. cf. amphitropous, campylotropous, hemitropous, orthotropous.

androdioecious: of plants, having bisexual flowers and male flowers on separate plants. cf. andromonoecious, dioecious, monoecious, polygamodioecious, polygamomonoecious, polygamous.

androecium: a collective name for the stamens, the male part of the flower. cf. gynoecium.

androgynaecandrous: inflorescence with male flowers above and below female flowers, as in the spikes of some species of Carex.

androgynophore: a stalk bearing both the stamens and superior ovary, e.g. in Passifloraceae. cf. gynophore.

androgynous: inflorescence with male flowers above female flowers, as in the spikes of some species of Carex.

andromonoecious: of plants, having bisexual and male flowers on the same plant. cf. androdioecious, dioecious, monoecious, polygamodioecious, polygamomonoecious, polygamous.

anemophilous: pollinated by wind.

angiosperms: the flowering plants; plants with ovules enclosed in an ovary.

annual: a plant completing its life cycle within one year from germination to fruiting and then dying.

annular: ring-shaped.

annulus: the elastic ring of cells that initiates dehiscence in the sporangium of a fern.

anomalous: irregular; abnormal.

anterior: away from the axis, toward the subtending (enclosing) bract. cf. posterior.

anther: the pollen-bearing part of the stamen, most often 2-locular with the loculi (pollen cavities) joined by the connective. Fig. 20 A–E.

antheridium: the fertile organ of a male gametophyte or the male organ of a bisexual gametophyte, in which male gametes are formed. cf. archegonium.

anthesis: the time of flowering; the time when pollen is shed.

anthocarp: a false fruit consisting of the true fruit surrounded by the base of the perianth, as in Nyctaginaceae.

anthotelic (= determinate inflorescence): an inflorescence with the inflorescence or parts of the inflorescence ending in a flower or an aborted but distinctly floral bud, e.g. panicle, thyrsoid, dichasium, monochasium, Fig. 17 A, B, D & E. cf. indeterminate.

antipetalous: opposite the petals.

antisepalous: opposite the sepals.

antrorse: turned towards the apex, e.g. of hairs. cf. retrorse.

apetalous: without petals.

apex: the tip. pl. apices.

apical: of the apex or attached at the apex or top, e.g. ‘ovules attached to an apical placenta’. Fig. 13 G.

apiculate: with a small abrupt point which is demarcated from the organ to which it is attached, e.g. of some anthers.

apiculum: a short, abrupt, flexible point. adj. apiculate.

apocarpous: a gynoecium consisting of two or more carpels which are free and distinct from each other, e.g. as in Ranunculaceae and Dilleniaceae. cf. syncarpous.

apomixis: the process whereby a plant produces viable seed without fertilization. adj. apomictic.

appendage: an attachment developed on and projecting from the surface of an organ, e.g. anthers Fig. 20 H.

appendiculate: with a small appendage or projection.

appressed: pressed closely against another organ, e.g. of hairs on a leaf.

approximate: growing close together; almost so.

aquatic: living in water.

arborescent: tree-like.

archegonium: a multicellular female sex organ producing and surrounding the egg.

arcuate: curved like a bow.

areolate: of surface pattern or venation, divided into many angular or squarish spaces, e.g. the venation and surface pattern in dried specimens in many Lauraceae. Fig. 9 I.

areole: (1) in Cactaceae, a cluster of hairs and/or spines borne at the node of a leafless stem; (2) a space in any reticulated surface, e.g. space between veins. adj. areolate.

aril: an expansion of the funicle into a fleshy or membranous appendage, sometimes partially or wholly covering the surface of the seed, and often brightly coloured, as in some Sapindaceae. Fig. 19 C. adj. arillate.

aristate: having a stiff, bristle-like awn or tip. Fig. 6 B.

aristulate: with a minute bristle.

armed: with spines and/or prickles.

article: (1) part of an organ which separates readily from the rest of an organ, e.g. as in a lomentum; (2) portion of branchlet between whorls of teeth in Casuarinaceae.

articulated: jointed; usually separating at the point of articulation into segments or articles, e.g. see unifoliolate leaf.

ascending: at first spreading horizontally and then becoming erect. Fig. 1 B.

asexual: without that part of the life cycle which involves fertilization and meiosis.

asperate: rough with hairs or points.

asymmetric (oblique): of a leaf, leaf base or other organ, having the sides unequal. Fig. 7 E.

atropous: see orthotropous.

attenuate: narrowing gradually. Fig. 7 A.

auct. non: (auctorum non., Latin) not of author; used to indicate that the preceding name has been misapplied by certain authors and is not that described by the succeeding authority.

auricle: (1) an ear-like outgrowth at the base of the sheath of some grasses and other monocots; (2) an ear-shaped lobe at the base of a leaf or other organ. adj. auriculate. Fig. 7 G.

autotrophic: independent of other organisms in respect of organic nutrition, able to form carbohydrates by process of photosynthesis. cf. parasite.

awn: a bristle-like appendage terminating an organ or inserted on its back. adj. awned. cf. aristate.

axil: the upper angle between one part of a plant and another part, e.g. the stem and a leaf, primary and secondary veins. adj. axillary.

axile: (1) on the axis; (2) of placentation, with the placentas and ovules along the central axis of the ovary in a compound ovary with septa, Fig. 13 C & D.

axillary bud: the bud or buds formed in the angle between the stem and the subtending (enclosing) leaf or bract.

axis: the central stem of a plant or an inflorescence, or the elongated part of the receptacle on which floral organs are situated.

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