Glossary of Botanical Terms:

C3 plants: plants that use the C3 pathway of carboxylation and do not have specialized Kranz anatomy, i.e. the majority of autotrophic plants. See also Kranz anatomy.

C4 plants: plants that use the C4 pathway of carboxylation and have specialized Kranz anatomy. See also Kranz anatomy.

caducous: falling early, e.g. of stipules. cf. deciduous.

caespitose: growing in tufts.

callosity: a thickened and hardened swelling on the surface of an organ.

callus: (1) a small hard protrusion, e.g. on the labellum of some Orchidaceae; (2) a hard point below the lemma, in spikelets of Poaceae; (3) a protective layer of tissue formed over an injury. pl. calli.

calyculus: the collective term for the involucral bracts (or phyllaries) surrounding a head in the Asteraceae.

calyptra (operculum): a cap-like covering or lid of some flowers or fruits that becomes detached at maturity by abscission; e.g. (1) the cap on the buds of eucalypts, (2) the lid of circumsciss capsules.

calyptra scar: scar left when the calyptra has fallen away, as in eucalypt fruits.

calyx: the sepals of one flower collectively. pl. calyces.

calyx tube: a tube formed by the fusion of the sepals, but sometimes wrongly used in the sense of hypanthium.

cambium: the meristem (growing region) in woody stems and fruits that forms the woody tissue.

campanulate: bell-shaped.

campylotropous: of an ovule, with the body bent or curved to one side so that the micropyle is near the funicle; the embryo sac is curved. Fig. 21 C. cf. anatropous, amphitropous, hemitropous, orthotropous.

canaliculate: with a longitudinal groove or channel.

canescent: whitish or pale grey, usually from a covering of short fine hairs.

canopy: (1) the branches and foliage of a tree; (2) often used as a collective term for the crowns of trees in a forest.

capillary: slender, hair-like.

capitate: (1) shaped like a head; (2) in a head-like cluster.

capitulum (head): a dense cluster of more or less sessile flowers, e.g. in Asteraceae a group of florets sessile on a common receptacle. Fig. 17 O & P.

capsule: a dry dehiscent fruit derived from two or more carpels. Capsules may dehisce in various ways. Fig. 18 L–P. adj. capsular.

carina: a keel. adj. carinate.

carnivorous: capable of trapping and digesting animals.

carpel: a unit of the female part of the flower (gynoecium), consisting of an ovary bearing one or more ovules, a receptive stigma, and often a stalk-like style between them. A flower can have a solitary carpel (and then the terms gynoecium and pistil are synonymous, Fig. 13 A & G) or more than one carpel. If the carpels (pistils) are free the gynoecium is apocarpous or if the carpels are fused the gynoecium (pistil) is syncarpous (or compound).

carpodium: a sterile female flower in which the ovary and ovule is reduced into a club-shaped structure with a short style but lacks the expanded stigma, as in Typha.

carpophore: in a fruit, the stalk of a mericarp. Fig. 18 H.

cartilaginous: hard and tough; gristly.

caruncle (strophile): an appendage of a seed, near the hilum (scar). Fig. 19 D. adj. carunculate.

caryopsis: a dry, indehiscent 1-seeded fruit in which the seed is fused to the wall of the fruit, as in family Poaceae. Fig. 18 S.

cataphyll: (1) a scale leaf associated with a vegetative part of a plant; (2) a leaf composed mostly of a leaf sheath or base with the lamina reduced to a minute awn, e.g. in some Juncus species.

catkin: a dense spike-like inflorescence, usually pendulous, with minute unisexual flowers.

caudate: bearing a narrow tail-like appendage.

caudex: a thick, erect trunk above and/or below ground level, e.g. in cycads.

caudicle: the stalk for a pollinium derived from the anther (as in some orchids); an elastic extension of some pollinia.

caulescent: with a trunk.

cauliflory: the production of flowers or fruits on well-developed trunks or major branches. adj. cauliflorous. cf. ramiflory.

cauline: borne on the more or less elongated aerial portion of a stem, e.g. describing leaves. cf. radical.

cell: the basic unit of plant structure consisting, at least when young, of a protoplast surrounded by a wall.

centrifixed: of a two-branched organ attached by its centre, e.g. a hair.

centrifugal: directed, or developing, from the centre or axis outwards. cf. centripetal.

centripetal: directed, or developing, from the outside towards the centre or axis. cf. centrifugal.

chaff: (1) membranous scales or bracts; (2) thin dry unfertilized ovules among the fully developed seeds of a fruit, as in many eucalypts.

chalaza: the part of an ovule to which the end of the stalk (funicle) is attached. Fig. 21. adj. chalazal.

channelled: with edges curved round (like a gutter).

character: any feature of an organism or taxonomic group that can be measured, counted or otherwise assessed.

chartaceous: papery, opaque and thin.

chasmogamous: of flowers that are pollinated while open. cf. cleistogamous.

chlorophyll: pigment(s) constituting the green colouring matter in plants and absorbing radiant energy in photosynthesis.

chromosome: a thread-like structure in the nucleus of a cell, containing a linear sequence of genes.

cilia: hairs more or less confined to the margins of an organ. sing. cilium. adj. ciliate.

ciliate: having the margin fringed with hairs, resembling an eyelash. Fig. 14 I. cf. fimbriate.

ciliolate: having the margin minutely fringed.

cincinnus: a tight, modified helicoid cyme with short pedicels on the developed side.

circinate (circinnate): spirally coiled with the tip innermost as in the young fronds of many ferns. Fig. 11 A.

circular (orbiculate): a 2-dimensional shape with length and breadth more or less equal. Fig. 5 E.

circumsciss (circumscissile): breaking open along a transverse line so that the top (calyptra) comes off like a lid, as in some capsules. Fig. 18 O.

cladode: a photosynthetic stem whose foliage leaves are usually reduced or absent.

clasping: surrounding or embracing, e.g. stem-clasping, of a lamina surrounding the stem.

class: a major taxonomic rank, between order and division.

classification: the establishing and defining of systematic groups; the assignment of organisms (plants) to groups within a system or hierarchy or ranks or categories. cf. systematics, taxonomy.

clathrate: latticed.

clavate: club-shaped.

claw: a narrow, stalk-like basal portion of a petal, sepal or bract. cf. limb.

cleistogamous: of flowers that remain closed and are self-pollinating and set fertile seed. cf. chasmogamous.

cleistogene: specialized florets produced at the base of some grasses in the leaf sheaths. These modified florets produce fertile diaspores without opening and they are different in appearance and structure from those in the inflorescence.

cline: continuous morphological variation in form within a species, or sometimes, between two species. adj. clinal.

clone: genetically identical organisms produced from a single parent by vegetative reproduction , or by development of ovules without fertilization.

closed forest (rainforest): a forest dominated by broad-leaved trees with dense crowns that form a continuous layer (canopy) and with one or more of the following growth forms.

club: of orchids (family Orchidaceae) when perianth segment swollen apically and that portion often covered in glands or glandular hairs.

cluster bract: a bract subtending a cluster of flowers.

coalesced: with like or unlike parts or organs partially fused in a more or less irregular fashion. cf. adhesion, adnate, cohesion, connate.

cobwebbed: covered with long weak, loosely entangled hairs, resembling a spiderweb; usually whitish. adj. cobwebby.

coccus: one of the segments (usually 1-seeded) of a distinctly lobed fruit which becomes separated at maturity; sometimes called a mericarp. Fig. 18 H & P. pl. cocci.

cohesion: the sticking together of two or more similar parts that are not organically fused. adj. coherent. cf. adhesion.

collateral: situated side by side; adjacent and on the same radius of an axis.

colliculate: of a surface, rough with low rounded protuberances. Fig. 16 A.

columella: the persistent central axis in some fruits and cones.

column: (1) (gynostemium) a structure formed by the union of stamens, style and stigmas, as in Orchidaceae, Asclepiadaceae and Stylidiaceae; (2) the lower part of an awn in grasses, when different in form from the upper part.

coma: a tuft of hairs, especially on a seed or fruit.

community: an assemblage of plants that naturally occur together.

complicate: folded together.

compound: composed of several more or less similar parts, as opposed to simple; e.g. of an ovary formed from several united carpels or of a leaf divided into leaflets. Fig. 3 A–F, I–M.

compressed: flattened in one plane, either dorsally (bringing the front and back closer together) or laterally (bringing the sides closer together).

concavo-convex: concave on one side and convex on the other.

concolorous: with the same colour throughout or on both surfaces. cf. discolorous.

conduplicate: folded flat together lengthwise, e.g. as in aestivation. Fig. 11 C.

cone: (1) a group of sporophylls arranged tightly on a central axis, as in cycads and conifers

conflorescence: a branch system bearing flowers in which the main axis bears uniflorescences, but is itself qualitatively different in structure from the uniflorescences.

confluent: merging or blending together.

conical: cone-shaped, with the broad end at the base.

connate: fusion of similar parts, e.g. petals into a corolla tube. cf. adnate.

connivent: coming into contact or converging.

connective: the sterile part of an anther connecting the loculi.

conspecific: belonging to one and the same species.

contiguous: touching but not fused, adherent, or coherent.

contorted: twisted; a form of imbricate aestivation in which each segment has one edge overlapping the next segment. Fig. 11 E.

contraligule: a tongue-shaped structure produced at the apex of the leaf sheath opposite the blade in Scleria.

convolute: rolled with margins overlapping. Fig. 11 D.

coppice shoot: a shoot developed from a dormant bud in the trunk or larger branches of a tree, the leaves on such a shoot often differ from the adult leaves and are called juvenile leaves (similar to sapling leaves); a common feature of many eucalypts and rainforest trees. Coppiceshoots usually develop after damage to the trunk by fire, cutting etc. Fig. 1 G.

cordate: of a leaf or leaf base, heart-shaped with a basal notch. Fig. 7 F.

coriaceous: leathery.

corm: a short, broad, fleshy, subterranean stem which produces aerial stems, leaves and flowers and in which food reserves are stored.

corolla: the petals of a flower collectively, frequently brightly coloured or white.

corona: any ring of tissue or appendage that stands between the perianth and the stamens, or on the perianth. e.g. as in Passiflora species.

cortex: the region of a stem or root surrounding the vascular cylinder but inside the epidermis.

corymb: an inflorescence (without a terminal flower) in which all the flowers are at the same level even though the pedicels arise at different levels. Fig. 17 K.

costa: a rib. adj. costate.

cotyledon: the first leaf or leaves of the embryo, present in the seed.

coumarin: a carbohydrate with a strong smell, as in some seeds and leaves.

crenate: of a margin, with shallow, rounded teeth. Fig. 8 B.

crenulate: finely crenate.

crested: with a terminal ridge or tuft.

crisped: very strongly, and usually finely, wavy. Fig. 8 I. cf. undulate.

crown: the part of a tree or shrub above the level of the lowest branch.

crustaceous: hard, thin and brittle.

cryptogam: a plant whose sexual reproductive parts are not conspicuous; a plant that produces spores, not seeds, in its sexual reproductive cycle, e.g. ferns, mosses, algae. cf. phanerogam.

cuboid: cube-like; a 3-dimensional shape.

cucullate: hooded.

culm: an aerial stem bearing the inflorescence, in grasses, rushes etc.

cultivar: cultivated variety, a variety developed in cultivation. An assemblage of cultivated individuals distinguished by any characters significant for the purposes of agriculture, forestry or horticulture, and which, when reproduced retains its distinguishing features.

cuneate: wedge-shaped, e.g. of a leaf or leaf base. Fig. 7 B.

cupule: a small cup. adj. cupular.

cupuliform: cup-shaped.

cusp: sharp, rigid point.

cuspidate: tapering into a sharp rigid point.

cyathium: an inflorescence of reduced unisexual flowers surrounded by involucral bracts, e.g. in Euphorbia species. Fig. 17 R.

cylindric: tubular or rod-shaped.

cyme: an inflorescence in which the main axis ends in a flower and further growth of the inflorescence is by one or more branches which themselves end in a flower (the main and lateral branches may bear bracteoles but have no bracts, leaves or nodes). adj. cymose. e.g. dichasium, monochasium. Fig. 17 D & E.

cymule: a small dichasium.

cypsela (an achene): the fruit formed in most Asteraceae; a dry indehiscent 1-seeded fruit formed from inferior ovary of 1 carpel, with the seed not fused to the fruit wall and usually topped by the pappus. Fig. 18 R.

cystoliths: mineral concretions, usually of calcium carbonate on a cellulose stalk, chiefly occurring in specialized hairs in some Urticaceae and Cannabaceae and in Acanthaceae; often appearing as tubercle-based hairs. Fig. 15 B.

deciduous: (1) falling seasonally, e.g. of the leaves and bark of some trees, cf. caducous; (2) a plant losing its leaves for part of the year, cf. evergreen.

decompound: several times divided, compounded, e.g. of inflorescences where the order of branching is more than just the once compound.

decorticating: with bark peeling off.

decumbent: spreading horizontally with the ends growing upwards. Fig. 1 J.

decurrent: extending downwards beyond the point of insertion, e.g. of a petiole extending down the stem as a ridge. Fig. 4 C.

decurved: bent downwards and curved. cf. deflexed.

decussate: in pairs, with successive pairs borne at right angles to each other. Fig. 2 D.

definite: of a constant number; e.g. twice as many stamens as the petals or sepals (or less), or an inflorescence ending in a flower or an aborted floral bud. cf. indefinite.

deflexed: bent sharply downwards. cf. reflexed, decurved.

dehiscent: opening at maturity to release the contents, e.g. of a fruit, anther etc.

deltate: a 2-dimensional triangular shape.

deltoid: triangular, but a 3-dimensional solid.

dendritic: much branched, like the crown of a tree, e.g. of hairs. Fig. 15 F.

dendroid: tree-like in form but not in size. cf. arborescent.

dentate: toothed with rounded or sharp course teeth.

denticulate: finely toothed.

depauperate: impoverished.

depressed: flattened as if pressed down from the top or end, especially of 3 dimensional shapes.

determinate: (1) of growth or branching, with a bud or flower terminating the main axis; (2) of an inflorescence (= anthotelic), 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.

diadelphous: having the stamens united by their filaments into two groups, as in Fabaceae subfamily Faboideae. Fig. 20 F. cf. monadelphous.

diagnosis: a detailed description.

diaspore: the dispersal unit containing the results of sexual reproduction and including non-floral parts (if any)

dichasium: a cyme in which branches appear in regular opposite pairs. Fig. 17 D. cf. monochasium.

dichlamydeous: of a flower, having two whorls of perianth parts, a distinct calyx and corolla. cf. monochlamydeous.

dichotomous: divided into two equal forks, e.g. of the branching pattern of stems or veins. Fig. 9 G.

dicotyledons: a major group of angiosperms (flowering plants) characterized by the embryo usually having two (rarely more) cotyledons (seed leaves). cf. monocotyledons.

didymous: with stamens in 2 equal pairs.

didynamous: in 2 pairs of unequal length.

digitate (palmate): of a compound leaf with 3 or more leaflets arising from one point at top of petiole, Fig. 3 E.

dimorphic: occurring in two different forms.

dioecious: with male and female flowers on different plants. cf. monoecious.

diploid: having two lots of the basic set of chromosomes in the nucleus. cf. haploid, polyploid.

disarticulate: to separate at a joint.

disc: an outgrowth of tissue from the receptacle in the form of a ring or plate, sometimes divided into lobes or separate bodies, occurring between whorls of floral parts; generally glandular.

disc floret (disc flower): usually an actinomorphic flower produced in the central part of the head and with a tubular corolla with more or less equal lobes, as in most Asteraceae. cf. ray floret.

discoid: (1) disc-shaped, flat and circular; (2) having only disc florets.

discolorous: coloured differently on the two surfaces. cf. concolorous.

disjunct-opposite: a variant of opposite and decussate leaf arrangement in which during development the leaves of a pair become separated on the axis owing to elongation of the nodal region, often giving the appearance of ‘alternate’ leaf arrangement but distinguished by decussate, not spiral, sequence.

dissected: divided at least partially into segments.

distal: towards the free end or apex, away from the point of attachment.

distichous (2-ranked): arranged in two rows on opposite sides of a stem and in the same plane. Fig. 2 B.

distinct: separate, free.

diurnal: of flowers, opening only during daylight hours. cf. nocturnal.

divaricate: broadly spreading, more or less horizontal. Fig. 1 E.

division: the major taxonomic rank within the plant kingdom (in which the phylum is no longer generally recognised). cf. phylum

domatia: small structures on the lower surface of some leaves, usually consisting of depressions, partly enclosed by leaf tissue or hairs, usually located in the axils of the primary and secondary veins. Fig. 19 A & B.

dorsal (abaxial): relating to the back of an organ, i.e. the surface of a lateral organ facing away from the axis. cf. ventral.

dorsifixed: attached at or by the back. cf. basifixed, versatile.

dorsiventral: term describing leaves in which the upper and lower surfaces differ from each other in texture, presence of hairs, stomates etc. cf. isobilateral.

doubly toothed: with smaller regular teeth on the margins of larger teeth, as in some Prunus species. Fig. 8 D.

drupaceous: term describing a fruit which is a drupe or drupe-like.

drupe: an indehiscent succulent fruit derived from a single carpel in which the pericarp consists of three layers

drupelet: one drupe of a mature fruit composed of a cluster of small drupes, as in blackberries, the ‘seed’ being a pyrene. Fig. 18 X.

dry sclerophyll forest: an open forest in which scleromorphic (hard-leaved) shrubs form a layer below the trees (usually species of eucalypts). cf. wet sclerophyll forest.

duplicate: folded twice.

dyad: in twos, a pair.

ebracteate: without bracts.

echinate: spiny; bearing stiff, stout, prickly hairs.

ecotype: a plant or group of plants exhibiting certain characteristics of growth or flowering in response to particular environmental conditions.

edaphic: pertaining to the soil.

eglandular: without glands.

elaiosome: an oil body on some seeds; a feature of some seeds dispersed by ants.

ellipsoid: the 3-dimensional equivalent of elliptic.

elliptic: a 2-dimensional shape, oval in outline, broadest about the middle. Fig. 5 D.

elongate: lengthened; stretched out.

emarginate: having a broad shallow notch at the apex. Fig. 6 G.

embryo: the rudimentary plant present in a mature seed or within the archegonium after fertilization and some development.

embryo sac: the female gametophyte, produced within the ovule. Fig. 21.

emergent: of a plant, (1) rising above the surrounding plants, e.g. of a tree above the rainforest canopy; (2) rising above the surface of the water.

enation: epidermal outgrowth, projection.

endemic: having a natural distribution confined to a particular geographic region. cf. native.

endocarp: the innermost layer of the pericarp. cf. exocarp.

endosperm: nutritive tissue within the seed, usually surrounding the embryo or to one side of it, and formed within the embryo sac (in angiosperms a product of accessory fertilization). cf. perisperm.

entire: of a margin, neither dissected nor toothed. Fig. 8 A.

entomophilous: pollinated by insects.

ephemeral: short-lived annual.

epi-: a prefix: upon, as in epipetalous = borne on the petals.

epicalyx: a whorl of bracts just below the flower, resembling an extra calyx.

epicarp: the outermost layer of the pericarp.

epicormic: term describing buds, shoots or flowers borne on the old wood of trees, often applied to shoots arising from dormant buds after injury or fire, as in eucalypts.

epidermis: the outer layer of cells of an organ.

epigeal: of germination, having the cotyledon(s) emerging from the seed coat and becoming photosynthetic. cf. hypogeal.

epigynous: of floral parts, especially stamens, inserted on or above the ovary, and arising from tissue that is fused to the ovary wall. Fig. 12 B. cf. hypogynous, perigynous.

epilithic: of plants growing on rocks, e.g. some orchids.

epimatium: the ovule-bearing scale in some conifers, as in Podocarpus species.

epipeltate: of an anther that is dorsifixed (peltate) and in which the part of the anther that is prolonged downwards beyond the attachment point of the filament faces inwards in relation to the centre of the flower. cf. hypopeltate.

epipetalous: borne on the petals.

epiphyllous: growing on leaves, as plantlets on the leaves in some Crassulaceae.

epiphyte: a plant perched, but not parasitic, on another plant. Fig. 1 I. cf. lithophyte.

episepalous: of stamens, borne on the sepals.

equitant: of leaves, folded longitudinally with the two inner surfaces (representing the upper leaf surface) fused except towards the base where it clasps another leaf on the opposite side of the stem; one margin represents the leaf keel and the lamina is vertically orientated; as in Iris. Leaf arrangement, Fig. 2 E; cross section through equitant arrangement Fig. 11 B.

erect: (1) upright, e.g. of a shrub, Fig. 1 A; (2) perpendicular to a surface, e.g. of hairs.

eremean: pertaining to regions of low, irregular rainfall.

ericoid: of leaves, small and sharply pointed like those of the heaths.

erose: of margins, irregular as if nibbled. Fig. 8 E.

espatheate: without spathes.

eusporangiate: of ferns, having sporangia with walls more than one cell thick, originating from a group of cells. cf. leptosporangiate.

evergreen: a plant bearing leaves throughout the year. cf. deciduous.

ex-: a prefix: without, e.g. exstipulate, without stipules.

excentric: not centrally placed, without a fixed centre.

excurrent: running through to the apex and beyond as a mucro, e.g. of the midvein in a leaf.

exine: the outer layer of a pollen grain or spore.

exocarp: the combined epicarp and mesocarp of a fruit. cf. endocarp.

exotic: introduced from outside the area concerned, in the case of N.S.W. usually from overseas.

exserted: projecting beyond the surrounding objects, e.g. of stamens protruding beyond the perianth, or of valves projecting beyond the rim of a capsular fruit. cf. included.

exstipulate: without stipules.

extrafloral: not within the flower, usually applied to nectariferous glands, e.g. as those on the petiole in some Croton species and on the phyllodes of some wattles. Fig. 19 E–H.

extravaginal: of a tiller that grows by breaking through the subtending leaf sheath as it grows. cf. intravaginal.

extrorse: of stamens, dehiscing towards the outside of the flower. cf. introrse, latrorse.

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