Glossary of Botanical Terms

Flora of South Australia

5th Edition | Edited by Jürgen Kellermann

Jessop, J.P., Toelken, H.R. & Kellermann, J. (2011). Glossary of botanical terms (version 1). In: Kellermann, J. (ed.), Flora of South Australia (ed. 5). 24 pp. (State Herbarium of South Australia: Adelaide). www.flora.sa.gov.au/ed5
State Herbarium of South Australia, DENR Science Resource Centre, PO Box 2732, Kent Town, SA 5071, Australia. Department of Environment and Natural Resources, Government of South Australia. ISBN 978-1-922027-16-0 (PDF). Publication date: 26 Oct. 2011.

Clicking on an underlined term or figure will copy or move that entry above the current definition.

 
abaxial
the parts of a flower or leaf furthest from the axis of the branch or stem on which it grows.
abortive
imperfectly developed.
accrescent
growing larger after flowering, as the sepals.
accumbent
of the radicle (in Brassicaceae seeds) when it lies against the appressed margins of the cotyledons.
achene
a dry indehiscent 1-seeded fruit. Figs 16E & F.
acicular
needle-shaped.
acropetal
produced in succession with the youngest nearest the apex of the supporting organ.
actinomorphic
a flower in which the segments of the perianth, or the parts of either of the two whorls of the perianth (calyx and corolla) are alike in size and shape (although in the latter case the two whorls need not have the same number of parts), and are arranged regularly round the axis. Such flowers are buttercup, poppy, Boronia, Geranium, Brassicaceae, etc. Figs 14A & B. See regular.
acuminate
tapering gradually into a point. Fig. 9B.
acute
sharp, gradually pointed. Fig. 9A.
adaxial
the parts of a flower nearest to the axis of the branch.
adnate
See connate.
adventitious
any organ produced in an abnormal position. For example, adventitious roots arise from stems and not as branches of other roots.
adventive
introduced accidentally or deliberately by humans to a specifies geographical area, as are most weeds.
albumen
material stored within the seeds of many plants for the nourishment of the embryo; it lies between the seed-coats and the embryo-sac (perisperm), or within the embryo-sac (endosperm).
alternate
(1) leaves or flowers inserted individually at different heights along the branches.
(2) intervening between; as stamens which are between rather that opposite the petals in most flowering plants.
amphitropous
when the ovule is laterally attached to the funicle, so that the chalaza and micropyle are at opposite ends of the ovule.
amplexicaul
with the base (of a leaf) clasping the stem.
anadromic
with the first veins or pinnule of a pinna on the side towards the apex.
anastomosing
applied to veins of a leaf joined by cross veins to form a network.
anatropous (inverted)
when an ovule is bent back along its funicle, so that the micropyle stands at the apparent base of the ovule and the chalaza at the opposite end (the apparent summit). Owing to the presence of the rhaphe the hilum of the seed does not coincide with the chalaza, but lies close to the micropyle. This is the commonest form of ovule.
androecium
a collective name for the stamens.
androgynous
when male and female flowers are mixed in a spike or head.
androgynophore
a column composed of an ovary on a long stalk to which the stamens are attached. The staminal filaments form a connate tube and the stamens continue past the ovary and the free parts hold the anthers (Passifloraceae).
andromonoecious
male and bisexual flowers developing on different individuals.
angiosperms
plants having seeds enclosed in a seed vessel.
annual
a plant flowering and dying in one year.
annular
ring-shaped.
anterior
see abaxial.
anther
see stamen.
antheridium
the male reproductive organ, as occurs in the gametophytes of ferns.
anthesis
the time of flowering.
antrorse
turned towards the tip of the supporting organ.
apiculate
ending abruptly in a short point; nearly the same as mucronate.
apocarpous
a pistil or gynoecium consisting of one carpel, or of several carpels all free and distinct (Ranunculaceae, Dilleniaceae). Fig. 14A.
apomictic
reproducing without the fusion of sexual gametes.
appressed
pressed closely against another organ, as leaves against a stem.
approximate
growing near together.
arborescent
tree-like.
archegonium
the female reproductive organ, as occurs in the gametophytes of ferns.
arcuate
curved.
aril
an expansion of the funicle into a membranous or fleshy appendage, sometimes covering a considerable part of the seed.
aristate
with a stiff awn or seta. Fig. 9C.
article
part of an organ which separates easily from the rest of the organ at a point called the articulation or joint.
articulate
jointed.
ascending
spreading horizontally and then becoming erect. Fig. 1A.
asperulate
minutely rough.
attenuate
narrowing gradually. Fig. 8C.
auricle
ear-shaped lobe at the base of a leaf or other organ. Fig. 8B.
auxotelic
an inflorescence axes not ending in a flower, which continue growth beyond the flowering region, sometimes causing the peduncle and rachis of the inflorescence to become somewhat elongated.
awn
a fine bristle terminating on organ or inserted on its back, used especially of the glumes and lemmas of the Gramineae.
axil
the angle formed by the leaf and the branch.
axile
placentas are axile when they and the ovules are attached to the inner angle (inner suture) of the carpels of a compound ovary. Fig. 15D.
axillary
arising from the axil of a leaf or a bract. Fig. 3A.
axis (plural axes)
line passing through the centre of a body: the stem, the rhachis and branches of a panicle, the rhachilla of grasses, are all axes.
 
Fig. 1. A, plant with ascending branches (Goodenia fascicularis); B, erect habit (Microtis unifolia); C, virgate habit (Choretrum chrysanthum); D, prostrate habit (Disphyma crassifolium); E, decumbent habit (Osteospermumfruticosum); F, procumbent habit (Vinca major); G, divaricate branching (Corynotheca licrota); H, dichotomous (strictly pseudodichotomous) branching (Gleichenia microphylla).
 
barb
one of the lateral or radial hairs of a plumose bristle.
barbellate
furnished with short, sometimes microscopic barbs, too small for the organ bearing them to be called plumose.
basifixed
an anther attached by its base to the filament; any organ attached by its base. Fig. 15G.
basipetal
produced in succession with the youngest nearest the base of the supporting organ.
beak
a pointed projection.
berry
a juicy fruit with the seeds immersed in the pulp. Fig. 16H.
biennial
a plant which flowers and dies in the second year.
bifid (2-fid)
cut in two for about half its length.
bifoliolate (2-foliolate)
a compound leaf of 2 leaflets. Fig. 5G.
bipinnate
applied to those leaves in which there are primary pinnate divisions (pinnae) which are themselves pinnate. Fig. 5C.
bipinnatifid
a leaf whose primary lobes are again pinnatifid.
bipinnatisect
twice pinnatisect.
bisexual
a flower with the reproductive organs of both sexes.
biternate
twice ternate. Fig. 5H.
bract
a small leaf at the base of the peduncles or pedicels, and differing from the other leaves in size or shape. Bracts may also occur on peduncles, scapes, or flowering branches without any pedicels in their axils.
bracteate
furnished with bracts.
bracteole
a small bract on the pedicel or even on the calyx. Bracteoles are usually two, and often placed opposite each other.
bristle
(1) a straight stiff hair, whether smooth or scabrous with minute teeth.
(2) in the grasses, the upper part of an awn, when the awn is bent and has a lower stouter, sometimes more hairy and usually twisted part, called the `column'.
bulb
a short thick and fleshy rootstock in which the bud or buds are covered by fleshy leaf-scales. Fig. 2F.
bulbil
a small bulb, especially when a plant has several of them. Sometimes loosely used for similar small corms.
bullate
blistered.
 
Fig. 2. A, underground rhizome (Schoenus nitens); B, stolon (Viola hederacea); C, root tubers (Thysanotus exiliflorus); D, stem tuber (Drosera whittakeri); E, corm (Hypoxis glabella); F, bulb (Calostemma purpureum).
 
caducous
falling off very early.
caespitose
tufted as, for example, in the tufted growth-form of some grasses.
callus
(1) a hard protuberance on some petals such as the standard of Swainsona and the labellum of some orchids,.
(2) a hardened decurrent extension of the lemma along the rhachilla in some grasses, such as Stipa: this callus and the adnate article of the rhachilla fall off with the fruiting lemma in the form of a short obconical stipes.
calyptra
a deciduous cap formed by fusion of perianth parts, covering stamens and carpels (e.g. Eschscholtzia). In Eucalyptus this is called operculum.
calyx (plural calyces)
outer envelope of the flower, consisting of free or united sepals.
campanulate
bell-shaped. Fig. 12A.
campylotropous
when an ovule is curved so that the micropyle and chalaza come near each other.
canaliculate
with longitudinal grooves.
capillary
hair-like, very slender.
capitate
(1) shaped like a head (stigma, etc.).
(2) growing in a head-like cluster (flowers of Asteraceae).
capitulum (or head)
a dense group of sessile flowers, especially a feature of Asteraceae. Fig. 13H.
capsule
a dry fruit (consisting of two or more united carpels,) usually splitting into pieces called valves when ripe, or opening at the summit by teeth or pores. Figs 16B-D, G.
carpel
a segment of the female reproductive element of a flower, the lower and swollen portion forms the ovary, inside which the ovules are produced; the upper and narrower portion forms the style and stigma. When there is only one carpel, the terms carpel, pistil, and gynoecium are synonymous; when more than one, the carpels may be free of one another or fused into a single structure.
carpophore
stalk or axis supporting certain fruits. See gynophore.
cartilaginous
gristly.
caruncle
a fleshy appendage of the seed, arising near the funicle.
cauda
a tail-like appendage.
caudex
a trunk-like axis surrounded by a mantle of roots, for example in Dicksonia.
caudicle
a strap-like structure connecting the pollen-masses in orchids to the viscid disk of the rostellum.
cauline
inserted on the stem. Fig. 1A.
cell
(1) the cavity of the ovary, and especially each cavity of a compound ovary or compound fruit.
(2) a pouch or pollen-sac of the anther (Fig. 15H).
(3) one of the minute masses of protoplasm which go to make up the tissue of plants.
centrifixed
a leaf, anther, branched hair or other organ attached by its centre.
centrifugal (or definite)
applied to that kind of inflorescence, such as a cyme, where the terminal flower opens first and then those on the lateral branches.
centripetal (or indefinite)
that kind of inflorescence, such as a head, spike, raceme, or panicle, where the outermost or lowest flowers open first and the main rhachis continues to lengthen, developing fresh flowers.
chalaza
see ovule.
channelled (or canaliculate)
with the edges curved round as in a gutter. Fig. 4J.
chartaceous
paper-like in texture.
chasmogamous
with pollination occurring in the open flower. See cleistogamous.
chelate
shaped like a lobster's claw.
ciliate
bordered by hairs like eye-lashes (cilia). Fig. 10A.
ciliolate
bordered by very short hairs.
circinate
coiled with the apex innermost as in the fronds of many fern species.
circumscissile
when a capsule opens by a transverse line, so that the upper part comes off like a lid. Fig. 16D.
clade
a group of organisms, whose members are derived from a common ancestor.
cladode
a shoot modified to assume the functions and usually the appearance of a leaf; often identifiable by arising in the axil of a modified leaf. Fig. 3F.
cladogram
a branching, tree-like diagram indicating the level of similarity between taxa, used as a representation of evolutionary (phylogenetic) relationships.
clathrate
latticed or pierced with apertures.
clavate
club-shaped.
claw
the narrow lower part of, for example, a petal or involucral bract.
cleistogamous
with pollination occurring within the closed flower. See chasmogamous.
clinandrium
the depression on the top of the column in orchids, on which the anther rests.
clone
a group of plants eventually able to exist on their own but originating from the vegetative growth of a common parent.
coenosorus
a compound sorus formed by the fusion of sori.
colleter
a group of mucilaginous secretory hairs, often near the base of the leaf lamina, and on calyx (Apocynaceae, Asclepiadaceae).
collateral
placed side by side.
colliculate
covered by low rounded protuberances. Fig. 11A.
column
(1) the combination of stamens and style in a solid body, as in orchids and Stylidiaceae.
(2) the lower usually twisted part of an awn in many grasses, passing into the bristle or slender upper part.
coma
an apical tuft, especially used for tufts of hairs on seeds or fruits.
comose
with an apical tuft of hairs.
complicate
folded flat together. See conduplicate.
compound
composed of several parts, as a leaf consisting of several leaflets, or a pistil consisting of several carpels; the opposite of simple. A compound panicle has the branches again divided.
compressed
flattened lengthwise, either from side to side (laterally) or from front to back (dorsally).
concolorous
of the same colour throughout.
conduplicate
see complicate.
cone
a fruit usually woody, ovoid or globular, consisting of scales arranged around an axis and sheltering the naked seeds, characteristic of the gymnosperms.
confluent
of two structures merging with one another.
connate
when organs are so closely united that they cannot be separated without tearing. Each of the connate parts is said to be adnate to the other.
connective
the part of an anther which connects the two cells.
converging (connivent)
organs approaching one another at the summit.
contorted
of the segments of a perianth whorl when in the bud each overlaps an adjacent one but is itself overlapped by the segment on its other side. Fig. 15B.
cordate
heart-shaped, with the notch below. Fig. 8G.
coriaceous
leathery; stiff, tough but somewhat flexible.
corm
a solid tuberous bulb-like stem (`rootstock'), in which the buds are not covered by scales, or by very thin ones. Fig. 2E.
corolla
inner envelope of the flower, consisting of free or united petals.
corona
a small crown of free or united appendages inserted inside the corolla and derived from the corolla or stamens. Fig. 14B.
corymb
inflorescence where the branches start from different points, but reach about the same height. Fig. 13D.
cosmopolitan
in plant distributions: occurring virtually world-wide.
costa
the midrib of a leaf.
costule
the midrib of a pinna or pinnule.
cotyledon
see embryo.
crenate
bordered by blunt or rounded teeth or small lobes. Fig. 10B.
crenulate
crenate with very small teeth or lobes.
crisped
finely curled (along the margin). Fig. 10C.
crustaceous
hard, thin and brittle.
cryptogam
plants without stamens, ovaries or seeds; that is the lower groups including the ferns.
cucullate
with the apex hood-like.
cultrate
shaped like a knife blade .
cuneate
wedge-shaped. Fig. 8D.
cusp
a rigid, usually small but sharp point.
cyme (adjective cymose)
an inflorescence in which the main axis ends in a flower and further growth of the inflorescence is by means of 1 or more branches which themselves end in a flower. This pattern may be repeated many times. Fig. 13E.
 
Fig. 3. A, twig (Eremophila sp.); B, opposite and decussate leaves (Plectranthus sp.); C, opposite and distichous (Euphorbia australis); D, equitant (Dianella revoluta); E, whorled or verticillate (Bauera rubioides); F, fascicled cladodes (Asparagus officinalis); G, imbricate (Azolla filiculoides).
 
deciduous
eventually shed.
decompound
applied to a compound leaf in which the subdivisions are again compound.
decumbent
with branches on the ground but turning up at the ends. Fig. 1E.
decurrent
when the base of the leaf is prolonged downwards along the stem in raised lines or narrow wings. Fig. 4K.
decussate
when one pair of opposite leaves arise at right angles to the pairs above and below them. Fig. 3B.
deflexed (decurved)
bent downwards.
dehiscent (dehiscing)
opening when ripe, as a seed vessel or anther.
deltoid
triangular, with the sides more or less equal.
dendroid (dendriform, dendritic)
used of hairs branched distally like the crown of a tree. Fig. 11B.
dentate
toothed. Figs 10D & E.
denticulate
finely toothed.
depressed
dorsally flattened along its length.
diad (or dyad)
a pair.
diadelphous
having the stamens in two groups (especially in most of the Papilionoideae, where 9 stamens are fused to one another and the tenth is free).
dichasium
a cyme in which branches appear in regular opposite pairs. Fig. 13E.
dichotomous
forking once or several times, each time into two equal branches. Fig. 1H.
diffuse
spreading horizontally and loosely branched.
digitate
a compound leaf whose leaflets spread from a common centre, like the fingers of a hand.
dimidiate
appearing as if one half were wanting. Fig. 6B.
dimorphic
occurring in two forms.
dioecious
male and female flowers developing on different plants.
diaphanous
permitting the light to shine through, translucent.
discrete
separate.
disk
(1) an extension of the receptacle between the calyx and pistil. It may be conspicuous in the form of a ring or cushion, or reduced to separate glands or scales.
(2) all the central or disk-flowers in a radiate flowerhead (applicable to many members of the Asteraceae).
dissepiment
one or more vertical partitions dividing the ovary and fruit into two or more cells. The dissepiment is usually caused by the adhesion of the sides of two adjoining cells or carpels. See septum.
distal
applied to the free end of, for example, a leaf, as opposed to the proximal or attached end.
distichous
regularly arranged in two opposite rows. Fig. 3C.
distinct
readily discernible; separate, free.
divaricate
with the branches spreading more or less at right angles from their point of attachement. Fig. 1G.
divergent
spreading from their point of attachement, but b y less than a right angle. See divaricate.
dorsal
relating to the abaxial side.
dorsifixed
an anther attached to the filament by its abaxial side. Fig. 15H.
dorsiventral
of leaves in which the adaxial and abaxial surfaces are clearly different from one another.
doubly dentate or serrate
when each tooth is itself again dentate (or serrate).
drupe
a fruit in which the pericarp consists of three layers: (1) the epicarp or skin, (2) the mesocarp or juicy layer, (3) the bony endocarp or stone: within the endocarp lies the seed or kernel. The peach and olive, and (among Australian plants) the fruit of Nitraria billardierei are familiar examples. Fig. 161.
 
Fig. 4. A, pinnatifid or lobed (Solanum hystrix); B, pinnatipartite (S. lacunarium); C, pinnatisect (Carinavalva glauca); D, palmatisect (Trachymene ornata); E, palmatifid (Ficus carica); F, recurved (Frankenia serpyllifolia); G, revolute (Muehlenbeckia horrida); H, incurved (Pultenaea tenuifolia); I, keeled (Eragrostis basedowii glume); J, channelled (Lomandra longifolia); K, decurrent (Pterocaulon sphacelatum); L, perfoliate (Cotula coronopifolia); M, gamophyllous (Eucalyptus gamophylla).
 
ebracteate
without bracts.
echinate
spiny.
ecostate
without a midrib.
elliptic
when a flat surface, such as that of a leaf, has regularly rounded ends and is broadest near the middle. Fig. 6C.
emarginate
notched at the summit. Fig. 9E.
embryo
the young plant while still enclosed in the seed, consisting of the radicle, or base of the future root, one or more cotyledons, or future seed-leaves, and the plumule, or future bud. The radicle always points towards the micropyle.
embryo-sac
see ovule.
endemic
peculiar to a country or district and not native elsewhere.
endocarp
the innermost layer of the pericarp.
endopleura
the inner seed-coat, sometimes called the tegmen.
ensiform
shaped like the blade of a sword.
entire
when the margin of an organ (such as a leaf) is neither toothed, lobed, or divided. Fig. 10F.
epicarp
see pericarp.
epigynous
when the sepals, petals and stamens are inserted upon the inferior ovary and the adnate torus or receptacle, as, for example, in Asteraceae and most Myrtaceae. Fig. 14B.
epipetalous
arising from the corolla.
epiphyte
one plant growing upon another, without deriving nourishment from it.
equitant
when a leaf is folded lengthwise and the edges adhere except at the base, where it clasps another leaf on the opposite side of the stem. Fig. 3D.
ericoid
heath-like in shape or habit.
erose
with the margin irregular as though nibbled.
estipellate
without stipels.
estrophiolate
without a strophiole.
exalbuminous
without albumen.
exindusiate
without an indusium.
exocarp
the combined epicarp and mesocarp of the fruit.
exserted
projecting beyond, as the stamens beyond the corolla, the awn beyond the glumes or the panicle, beyond the uppermost leaf sheath.
exstipellate
without stipels.
exstipulate
without stipules.
extravaginal
when the lateral shoot of a grass breaks through the subtending leaf-base.
extrorse
an anther which opens towards the outside of the flower.
 
Fig. 5. A, paripinnate (Atalaya hemiglauca); B, imparipinnate (Indigofera australis); C, bipinnate (Acacia mearnsii); D, palmately compound (Cannabis sativa); E, palmately trifoliolate (Cullen parvum); F, pinnately trifoliolate (C. patens); G, bifoliolate (Zygophvllum billardierei); H, biternate (Clematis microphylla).
 
falcate
curved like the blade of a scythe. Fig. 6D.
family
a group of genera (see genus) which resemble each other.
farinose
see mealy.
fascicle
a tuft of leaves or other structures apparently all arising at the same node. Fig. 3F.
ferruginous
rust-coloured.
fertile
(A) of flowers: producing seeds; (B) of anthers: containing pollen.
-fid
cleft.
filament
see stamen.
filiform
thread-like. When applied to leaf blades it means more slender than subulate, but of similar construction. Fig. 6E.
fimbriate
fringed. Fig. 10G.
fistula
the opening in a hollow leaf-base through which the stem emerges.
fistulose
hollow, like a pipe.
flabellate
fan-shaped. Fig. 6F.
flammuliform
term used to describe the complicated leaf division in some species of Clematis (derived from C. flammula); see treatment of Ranunculaceae for detailled explanation.
flavescent
yellowish.
flexuose
(of axes) bending backwards and forwards at alternate nodes.
floral leaves or leafy bracts
the upper leaves at the base of the flowering branches. In Rhamnaceae floral leaves are the leaves surrounding a head-like inflorescence, covered with a dense white indumentum.
floral tube
a tube bearing the perianth and stamens, made up of tissue derived from the receptacle and/or perianth and/or stamens.
floret
a small flower, especially when forming part of a dense inflorescence (e.g. in Asteraceae).
-foliolate
the number of leaflets to a compound leaf; e.g. a 5-foliolate leaf has 5 leaflets.
follicle
a fruit consisting of a single carpel opening only along the inner suture. Fig. 16J.
foveate (diminutive foveolate)
with small pits (foveae).
free
not united with any other similar organ.
free central placenta
one in the form of a central column rising from the base of the ovary, or consisting of a prolongation of the receptacle, and in both cases unconnected with the walls of the ovary. Primulaceae, Caryophyllaceae, Santalaceae. Fig. 15F.
frond
the fern leaf.
fruit
the enlarged ovary and whatever other parts of the flower may adhere to it at the time the seed is ripe.
funicle
a little stalk by which the ovule is attached to the placenta.
fuscous
dusky.
fusiform
spindle-shaped, tapering gradually at each end. Fig. 12B.
 
Fig. 6. A, deltoid (Thysanotus dichotomus bract); B, dimidiate (Adiantum capillus-veneris); C, elliptic (Anagallis arvensis); D, falcate (Eucalyptus incurva); E, filiform (Gyrostemon ramulosus); F, flabellate (Asplenium flabellifolium); G, lanceolate (Epilobium pallidiflorum); H, linear (Glischrocaryon behrii); I, lunate (Euphorbia lathyrus gland); J, lyrate (Arctotheca calendula); K, oblanceolate (Selliera radicans).
 
galeate
helmet-shaped.
gametophyte
a plant which bears sexual organs; in ferns usually a small but discrete plant very different from the sporophyte (which is the fern plant); in seed-plants reduced to a microscopic structure within an anther or ovary not recognisable as a discrete plant.
gamophyllous
of opposite leaves joined to one another around both sides of the stem. Fig. 4M.
geniculate
bent like a knee.
genus (plural genera)
a group of species which resemble each other.
gibbous
when an organ is swollen in one part, most frequently towards the base.
glabrescent
becoming glabrous gradually.
glabrous
devoid of hairs.
gland
a wart-like excrescence on or near the surface of an organ and usually secreting a substance, such as a fluid, gum or salt.
glandular hairs
hairs tipped with a gland. Fig. 11C.
glaucous
bluish-green, usually of a pale tint.
globose
almost spherical.
globular
rounded like a globe or sphere. Fig. 12C.
glochidium (plural glochidia)
a barbed bristle as on the fruit of some Apiaceae.
glomerule
a small dense cluster of flowers forming part of an inflorescence.
glume
bract enclosing the flower of reeds or one of two bracts at the base of a grass spikelet.
glutinous
sticky.
grain
the fruit of grasses, also called caryopsis.
granular
covered with small rounded protuberances.
gymnosperms
plants, such as pines, which produce ovules and seeds, but these are not enclosed in a carpel or fruit..
gynoecium
see pistil.
gynomonoecious
a plant with bisexual and female flowers.
gynophore
stalk supporting an ovary. See carpophore.
gynostemium
a column formed by the union of style and stamens.
 
Fig. 7. A, oblong (Euphorbia lathyrus); B, obovate (Polycarpon tetraphyllum); C, orbicular (Muehlenbeckia adpressa); D, ovate (Epilobium billardierianum); E, peltate (Hydrocotyle verticillata); F, reniform (Viola hederacea); G, rhomboid (Tetragonia tetragonioides); H, runcinate (Sonchus oleraceus); I, spathulate (Ptilotus spathulatus).
 
habit
the general external appearance of a plant.
habitat
the environment in which a plant lives.
hastate
shaped like a halbert, with two spreading somewhat triangular lobes at the base. Fig. 8E.
see capitulum.
helicoid cyme
a monochasium branching repeatedly on the same side so that the apex is often recurved or recoiled (cf. scorpioid).
herb
a plant which does not develop a woody stem.
herbaceous
green and relatively soft in texture.
heterogamous
when the outer flowers in a flowerhead are female or neuter, and the inner ones bisexual or male.
heterosporous
with spores of two kinds.
hilum
the scar left on the seed where it separates from the funicle.
hirtellous
minutely hirsute.
hispid
rough with short stiff hairs.
hoary
densely covered by almost microscopic hairs, which give the surface a whitish or greyish hue.
homogamous
when all the flowers in a flowerhead are bisexual.
homosporous
with spores of one kind only.
hyaline
delicately membranous and transparent.
hydrophilous
pollinated through the agency of water.
hypanthium
a tube formed by the floral receptacle and bearing the perianth and stamens.
hypocrateriform
shaped like a more or less circular tray with a central tubular base.
hypogynous
inserted below the (superior) ovary, as the sepals, petals and stamens in most flowering plants. Fig. 14C.
 
Fig. 8. A, obtuse (Malvastrum spicatum); B, auriculate (Goodenia amplexans); C, attenuate (Lysiana exocarpi); D, cuneate (Dodonaea bursariifolia); E, hastate (Acetosella vulgaris); F, sagittate (Fallopia convolvulus); G, cordate (Sida corrugata); H, oblique (Eucalyptus obliqua); I, truncate (Lasiopetalum discolor).
 
imbricate
overlapping like tiles (Fig. 3G); when the members of a perianth whorl in a bud overlap each other at the edges with one segment overlapped on both edges and another overlapping its adjacent segments on both sides. Fig. 15A.
imparipinnate
a pinnate leaf terminating in a single leaflet. Fig. 5B.
incised
deeply and unequally cut into lobes or teeth.
included
enclosed, as stamens within the corolla.
incumbent
leaning upon another organ; of the radicle (in Brassicaceae seeds) when it lies along the back of one cotyledon.
incurved
bent inwards. Fig. 4H.
indehiscent
a fruit which does not split open in a regular manner when ripe.
indumentum
surface covering such as hairs and scales.
induplicate
when the edges of petals or sepals are folded inwards in bud, but without overlapping.
indurate
hardened.
indusiate
possessing an indusium.
indusium
(1) a membrane covering the sporangia of some ferns (Fig. 17C).
(2) a cup enclosing the stigma in Goodeniaceae.
inferior
an ovary is inferior when it is united with the cup-shaped or tubular torus or receptacle; the calyx, petals, and stamens are then all superior to the ovary, or epigynous (Fig. 14B). An inferior radicle points towards the base of the fruit; an inferior (apotropous) micropyle points towards the base of the ovary.
inflated
swollen like a bladder.
inflorescence
arrangement of the flowers on a plant.
infructescence
an inflorescence in fruit.
innocuous
spineless.
integument
covering, one of the outer layers of tissue of an ovule.
interfoliar
between the leaves.
internode
the part of the stem between two nodes. Fig. 3A.
interpetiolar
of stipules placed between the petioles of opposite leaves.
interrupted
having bare spaces between the parts.
intravaginal
when the lateral shoot of a grass does not break through the subtending leaf sheath.
introrse
an anther which dehisces by slits facing the pistil and therefore turned inwards.
involucel
(1) the involucre of a partial umbel.
(2) the outer calyx in Dipsacaceae.
involucre
a number of bracts surrounding the base of a flowerhead or of an umbel.
involute (inrolled)
with the edges rolled inward, as in the leaf blades of many grasses.
irregular
this term is used in its strictest sense to describe those rare asymmetric flowers which cannot be divided into two equal halves through any vertical plane (such as the Valerianaceae). It is here applied in a more general sense to a flower in which the parts of either the calyx or corolla are dissimilar in size or shape. It therefore includes flowers, which are altogether asymmetric and those which are zygomorphic, or bilaterally symmetrical, i.e., which can be cut through only one vertical plane into two equal and similar halves (flowers of Papilionoideae, Pelargonium, Viola, etc.). Fig. 14C.
 
joint
see article.
 
keel
(1) a projecting ridge along the middle of a flat or convex surface (Fig. 41).
(2) the two partially united lowest petals of pea-shaped flowers.
kernel
see drupe.
 
Fig. 9. A, acute (Codonocarpus cotinifolius); B, acuminate (Salix babylonica); C, aristate (Sagina apetala); D, apiculate (Santalum spicatum); E, emarginate (Euphorbia lathyrus); F, obtuse (Clematis microphylla); G, uncinate (Santalum acuminatum); H, truncate (Panicum decompositum glume); I, obcordate (Stenanthemum Ieucophractum); J, mucronate(Indigofera uncinata); K, retuse (Abutilon theophrasti petal).
 
labellum
(1) the lowest petal of orchids, usually different in form from the two lateral ones.
(2) the lowest petal of Stylidiaceae.
labiate
lipped; where the limb of a corolla is divided into two parts, called an upper and lower lip.
lacerate
jagged, as if torn. Fig. 10H.
laciniate
cut into narrow lobes.
lamella
a thin plate.
lamina
the blade of a leaf, or the expanded upper part of a petal, sepal, or bract. Fig. 3A.
lanceolate
shaped like the head of a lance, tapering at both ends, but broadest below the middle. Fig. 6G.
leaflet
each division of a compound leaf.
lemma
the bract (glume) subtending the flower in grasses.
lenticels
small corky interruptions to the bark.
lenticular
more or less disc-shaped but convex on both sides.
lignotuber
a woody swelling at the base of the stem (especially in some Proteaceae or species of Eucalyptus).
ligulate
having the limb of the corolla strap-shaped, as in many Asteraceae.
ligule
(1) a small membranous appendage at the summit of the sheath of the leaves of Poaceae and a few other plants.
(2) the one-sided limb of the corolla in many Asteraceae.
limb
(1) the upper, often spreading part of a calyx or corolla; it is an expansion upwards of the tube or united part of the calyx or corolla.
(2) the lamina of a leaf or of a petal.
linear
long and narrow, with parallel edges. Fig. 6H.
lobe
division of a leaf reaching about half-way to the midrib, or of other organs, such as petals or sepals, which are partly fused.
lobed
(1) cut about half-way (Fig. 4A).
(2) a compound ovary or fruit which is deeply grooved between the carpels.
lobule
a small lobe.
loculicidal
when a ripe capsule splits open along the abaxial sides of its cells (i.e., along the midrib of the carpels), as in Juncaceae and Asparagaceae. Each valve into which the capsule splits consists of 2 halves of adjoining carpels, with the dissepiment attached along the centre of the valve. Fig. 16C.
loment
a legume contracted between the seeds.
long-creeping
in ferns a rhizome which elongates rapidly so that the fronds are usually distant.
lorate
strap-shaped.
lunate
crescent-shaped. Fig. 6I.
lyrate
a pinnatifid or pinnatisect leaf with a terminal lobe much larger than the lateral ones. Fig. 6J.
 
Fig. 10. A, ciliate (Adenanthos terminalis bracts); B, crenate (Melissa officinalis); C, crisped (Rumex crispus); D, finely and irregularly dentate (Sonchus oleraceus); E, coarsely dentate (Grevillea ilicifolia); F, entire (Alectryon oleifolius); G, fimbriate (Thysanotus juncifolius perianth); H, lacerate (Polygonum patulum stipules); I, repand (Commicarpus australis); J, serrate (Melianthus major); K, sinuate (Solanum elaeagnifolium); L, undulate (Potamogeton crispus).
 
mallee
one of the several-stemmed species of Eucalyptus, or the vegetation characterised by such species.
mamillary
nipple-shaped.
mamelon
a mound of tissue in the Loranthaceae ovary containing the ovules, which do not have true integuments.
marcescent
withering without being shed.
mealy (farinose)
covered with a scurfy powder like flour.
megasporangium
sporangium containing megaspores; not readily visible in flowering plants.
megaspore
spore giving rise to female gametophyte and egg cells.
megasporophyll
leaf associated with a megasporangium.
membranous
thin, transparent and flexible, not green.
mericarp
one of the segments into which some fruits (e.g. Geraniaceae) split.
-merous
the number of parts per floral whorl; e.g. Brassicaceae flowers are 4-merous.
mesocarp
the second or middle layer of the pericarp; often succulent and then sometimes called the sarcocarp. See drupe.
mesophyll
the internal tissues of a leaf.
micropyle
a minute opening in the coats of the ovule . In the great majority of plants the pollen-grain finds its way to the embryo-sac through the micropyle.
microsporangium
sporangium containing microspores.
microspore
spore giving rise to male gametophyte and sperm.
midrib
the central nerve of a leaf or similar organ. See costa. Fig. 4B.
monadelphous
with the stamens all fused to one another as in many Leguminosae.
moniliform
when a pod or other organ is constricted at regular intervals, so as to resemble a necklace of beads.
monochasium
a cyme in which a single axis develops below each flower; cf. a dichasium where two axes develop. For example Fig. 13F.
monoecious
male and female flowers developing on the same individual.
monotypic
having only one representative, e.g. a genus with only one species is monotypic.
mucronate
terminating abruptly in a short stiff point called a mucro. Fig. 9J.
mucronulate
minutely mucronate.
muricate
rough owing to many minute hard outgrowths.
muticous
of an apex lacking any projection such as a mucro or awn.
 
naked
flower without any perianth; seed without a pericarp.
native
of a texon that grows in a specific area without being brought into the area during recent times (usually through the agency of humans). See naturalised.
naturalised (*)
of a taxon that has originally been introduced by humans to an area deliberately or accidentally (from overseas, from other states in Australia or from other areas within S.A.), then has become established and is reproducing itself in a new environment. An asterisk (*) in front of the species or subspecific name indicates that a taxon is naturalised in S.A.; asterisks are also placed before each of the S.A. botanical regions or Australian states in which the plant is naturalised. See native.
nerves (veins)
the vascular bundles which start from the petiole and traverse the blade of the leaf, the smaller ones often forming a network.
node
the swollen part of the stem from which leaves or branches spring. Fig. 3A.
nut
properly a 1-seeded indehiscent fruit, such as the hazel-nut, with a hard dry pericarp (`shell'), but also used to describe any hard l -seeded nut-like fru it, such as those of Polygonaceae and Cyperaceae.
 
Fig. 11. A, colliculate (Calandrinia polyandra seed); B, dendriform hairs (Dicrastylis doranii branch); C, glandular hairs (Boerhavia coccinea branch); D, papillae (Gunniopsis septifraga leaf); E, reticulate (Schoenus apogon seed); F, rugose (Allocusuarina decaisneana cone); G, sessile glands (Chenopodium pumilio branch); H, stellate hairs (Pomaderris oraria leaf); I, tomentose (Amyema gibberula leaf); J, tubercle-based hairs (Eriachne artistidea glume); K, woolly (Malacocera tricornis branch).
 
ob-
a prefix indicating that a shape is the opposite way up to its usual position; e.g., turbinate means top-shaped with the broadest end uppermost; obturbinate means top-shaped but with its point uppermost.
obcordate
inversely heart-shaped, broad, and rather deeply notched at the summit. Fig. 8I.
oblanceolate
lanceolate with the narrow end at the base of the leaf. Fig. 6K.
oblique
slanting; (of a leaf) unequal-sided. Fig. 8H.
oblong
much longer than broad, and rounded at both ends. Fig. 7A.
obovate
ovate with the broadest part above the middle. Fig. 7B.
obovoid
egg-shaped (of solid organs such as fruits), with the broadest part towards the apex.
obtuse
blunt. Figs 8A & 9F.
operculum
the calyptra in the genus Eucalyptus.
opposite
(1) of two leaves or other organs rising at the same level, but on opposite sides of the stem (Figs 3B & C).
(2) of the members of two concentric floral whorls when they are on the same radii.
orbicular
flat, circular or almost so. Fig. 7C.
order
a group of families resembling each other.
orthotropous (atropous)
when an ovule has a straight axis , the chalaza being at its base and the micropyle at the opposite end. .
oval
elliptic (usually broadly so).
ovary
the lower part of the carpel or pistil, containing the ovules, and finally becoming the fruit. Compound ovary, see syncarpous.
ovate
when a flat surface, such as that of a leaf, is egg-shaped and broader below the middle. Fig. 7D.
ovoid
egg-shaped (of solid organs such as fruits), with the broadest part towards the base. Fig. 12D.
ovule
the seed in its early stage. It consists of the embryo-sac, containing the future embryo, completely surrounded by the nucellus, which is in its turn surrounded (except at the micropyle) by an outer covering, usually consisting of two coats, an inner and an outer. On the ovule are a spot called the chalaza, where nourishment enters from the placenta through the funicle, and a small opening through the outer covering, which is called the micropyle.
 
Fig. 12. A, campanulate (Lomandra densiflora); B, fusiform (Muehlenbeckia diclina seed); C, globular (Acacia pycnantha flower head); D, ovoid (Sagina maritima seed); E, rotate (Leptospermum myrsinoides); F, subulate (Scleranthus pungens leaf); G, terete (Amyema preissii leaf); H, trigonous (Maireana eriantha leaf); I, triquetrous (Choretrum chrysanthum young branch); J, urceolate (Erica baccans).
 
palea
the upper of two bracts enclosing the indivicual flower of grasses.
palisade tissue
a tissue of elongate chlorophyll-containing cells with their axes perpendicular to and just below the upper surface of most leaves.
palmatifid
leaf divided into diverging lobes , and so resembling the open hand. Fig. 4E.
palmatisect
palmately divided nearly to the base. Fig. 4D.
pandurate
fiddle-shaped.
panicle
an inflorescence where the axis is divided into branches bearing several flowers. Fig. 13C.
paniculate
arranged in a panicle.
papilionate
with a corolla like that of a pea (literally butterfly-like).
papillose
covered with minute protuberances called papillae. Fig. 11D.
pappus
a ring of hairs or scales which represents the calyx in many Asteraceae. Fig. 16F.
parasite
a plant growing on another, and deriving its nourishment from the latter.
parietal placenta
when the placentas and ovules are attached to the walls of a 1-celled compound ovary. Fig. 15E.
paripinnate
a pinnate leaf terminating in two opposite leaflets. Fig. 5A.
parted (partite)
an organ divided into parts almost to its base .
patent
spreading.
pectinate
arranged like the teeth of a comb.
pedicel
stalklet of a flower , when the peduncle bears two or more pedicellate flowers.
pedicellate
growing on a pedicel.
peduncle
stalk of a solitary flower, or common stalk (floral axis or rhachis) of several pedicellate or sessile flowers.
pedunculate
growing on a peduncle.
peltate
(1) leaf (or other flat organ, e.g. scales) whose stalk is attached to its under-surface, instead of to the edge (Fig. 7E).
(2) shield-like, pendulous ovule, one hanging from the summit of the ovary. The term suspended is sometimes used when the ovule is attached slightly below the summit.
penicillate
arranged like a tuft of hairs in a paint brush.
penninervation
with pinnately arranged veins.
perennial
living for several years .
perfoliate
with the base of the leaf fused round the stem so that the leaf appears to pass through it. Fig.4L.
perianth
the floral envelope, usually consisting of two whorls , the calyx and corolla. The term is specially employed to describe flowers in which the segments of the perianth (perianth-segments) are much alike but in whorls (as in Iridaceae and Juncaceae), or quite similar and in a single whorl (as in Chenopodiaceae).
pericarp
the walls of the fruit, consisting of the ripened ovary. The walls or layers may be more or less fused into one, or they may be easily distinguishable as three: the epicarp, mesocarp, and endocarp. In inferior fruits the concave receptacle remains adherent to the pericarp and forms part of the fruit. Combined epicarp and mesocarp are often called exocarp.
perigynous
when the sepals, petals and stamens are inserted round the superior ovary on the cup-like or tubular torus or receptacle. The stamens also appear perigynous when inserted on the corolla. Fig. 14D.
perisperm
that part of the albumen in a seed which is outside the embryo-sac.
persistent
lasting until the fruit is ripe, as sepals or glumes; also applied to leaves remaining green during the winter: the opposite of caducous and deciduous.
petal
one of the divisions or leaves of the corolla, usually coloured.
petaloid
resembling a petal.
petiolate
supported on a petiole.
petiole
stalk of a leaf. Fig. 3A.
petiolule
stalk of a leaflet. Fig. 5F.
phyllode
a flat dilated petiole, fulfilling the functions of a leaf, as in many acacias.
phylogeny
the evolutionary history of a taxon at any rank.
pilose
with soft hairs.
pilosulose
finely pilose.
pinna (plural pinnae)
a primary division of a pinnate leaf; a leaflet.
pinnate
a compound leaf whose leaflets are arranged on each side of the common petiole or axis. When there is an odd terminal leaflet, the leaf is called unequally pinnate or imparipinnate. Also applied to lateral nerves arranged on each side of the mid-nerve of a leaf.
pinnatifid
with the margin pinnately cleft. Fig. 4A.
pinnatipartite
cut more than half-way to the midrib. Fig. 4B.
pinnatisect
pinnately divided almost to the midrib. Fig. 4C.
pinnule
a secondary or tertiary division of a leaf.
pistil or gynoecium
the innermost and female part of the flower, consisting of one or more carpels. When there is only one carpel, the terms carpel , pistil, and gynoecium are synonymous. When two or more carpels adhere by their ovaries, the pistil or gynoecium is compound or syncarpous. When the carpels are separate the gynoecium is apocarpous.
pistillode
an abortive or rudimentary pistil.
placenta
part of the ovary to which the ovules are attached by their funicles . Figs 15D­F.
plano-convex
flat on one side and convex on the other.
plicate
pleated.
plumose
when a hair or similar organ branches into rather long spreading secondary hairs, arranged irregularly or in two opposite rows like the barbs of a feather.
pod
(1) the legume of Fabaceae, a dry fruit formed of a single carpel.
(2) the siliqua and silicule of Brassicaceae, a dry fruit composed of two carpels separated by a partition.
pollen
see stamen.
pollinium (pollen-mass)
pollen-grains cohering by a waxy texture or fine threads into a single body.
polygamo-dioecious
mainly dioecious but with some bisexual flowers on otherwise male and/or female plants.
polygamo-monoecious
mainly monoecious but with some bisexual flowers.
polygamous
when the same plant bears male, female and bisexual flowers.
polymorphic
occurring in several forms.
poricidal
of capsules opening by pores. Fig. 16G.
posterior
see adaxial.
prickle
sharp excrescence arising from the bark and detachable without tearing the wood.
procumbent
spreading along the ground, but not so closely as prostrate. Fig. 1F.
proliferous (viviparous)
plants which bear adventitious leaf-buds on the leaves or flowers, such buds being capable of rooting and forming separate plants.
prostrate
lying flat on the ground. Fig. 1D.
proximal
see distal.
pruinose
covered with a powdery waxy material.
pseudodichotomy
false dichotomy.
pseudostaminode
floral tissue that resembles a sterile stamen (staminode) or a staminal filament.
puberulent (puberulous)
downy.
pubescent
downy, covered with short soft hairs.
pulvinus
a swollen base of a petiole (e.g. in Acacia).
punctuate
marked with dots.
punctiform
like a point or dot.
punctulate
finely dotted.
pusticulate
with minute blisters.
putamen
a hard bony endocarp.
pyrene
1 or more `stones' containing the seed in a drupe or similar fruit.
pyriform
pear-shaped (of solid forms such as fruits).
 
quadrate
square or nearly so.
 
Fig. 13. A, raceme (Caesia calliantha); B, spike (Wurmbea dioica); C, panicle (Thysanotus baueri); D, corymb (Scilla peruviana); E, cyme (Gunniopsis septifraga); F, scorpioid cyme (Cynoglossum suaveolens); G, umbel (Burchardia umbellata); H, capitulum (Trifolium glomeratum).
 
raceme
an undivided axis or peduncle bearing pedicellate flowers. Fig. 13A.
racemose
arranged in a raceme.
radiate
flowerhead of Asteraceae which has ligulate flowers in the circumference and tubular flowers in the centre.
radical
arising from the root.
radicle
see embryo.
radicular
used, for example, for the slit in the perianth of Sclerolaena opposite the radicle and through which the germinating radicle emerges.
ray
(1) all the ligulate flowers (ray-florets) in a radiate flowerhead.
(2) each of the branches of an umbel.
receptacle
(1) floral axis, torus. The summit of the peduncle or pedicel on which the parts of a single flower are arranged, either in whorls or spirally. It may extend upwards as an annular or cushionshaped disk, and this may assume the form of glands or scales, which often alternate with the stamens (Rutaceae, Zygophyllaceae). It may be lengthened into a column or carpophore, such as those which bear the fruitlets of Geraniaceae and Apiaceae, or into a small stalk supporting the ovary (some Caryophyllaceae, Fabaceae, Proteaceae). It is very frequently hollowed out into a cup or rarely a tube, which surrounds the ovary and bears the sepals, petals and stamens on or near its margin, and is usually united with the ovary, or more rarely free from it (Myrtaceae, Rosaceae, Onagraceae, Thymelaeaceae). Formerly this hollow receptacle when united with the ovary, was described as the `adnate (adherent) calyx tube'.
(2) Floral base or common receptacle. The expanded summit of the peduncle on which the flowers, surrounded by an involucre of bracts, are inserted, usually in a dense cluster (Asteraceae, Dipsacaceae). In Asteraceae both forms of the receptacle are present.
recurved
curved backward or downward. Fig. 4F.
reduplicate-valvate
when the edges of petals or sepals are turned backward and outward in the bud.
reflexed
bent abruptly backwards.
regular
practically equivalent to actinomorphic, or radially symmetrical, i.e., where a flower can be bisected through two or more vertical planes into two similar halves.
reniform
kidney-shaped. Fig. 7F.
repand
with margins slightly sinuate. Fig. 10I.
replum
the rim of the pod of Brassicaceae, after the valves have fallen.
resupinate (reversed)
when a flower is inverted by a twisting of the pedicel or the ovary so that the parts usually uppermost become the lowest (e.g. in Thelymitra).
reticulate
when the nerves or veins cross each other like the meshes of a net. Fig. 11E.
retinacule
a marginal outgrowth from a spadix occurring in the Zosteraceae.
retracted
turned backwards.
retrorse
turned backwards.
retuse
with an obtuse apex the centre of which is shallowly notched. Fig. 9K.
revolute
when the edges of leaves are rolled backwards towards the midrib. Fig. 4G.
rhachilla
the rhachis of the spikelet in grasses and sedges.
rhachis
any principal axis of an inflorescence; also applied to the common petiole of a compound leaf.
rhaphe
a cord adhering to one side of an anatropous ovule and connecting the chalaza with the placenta. It is often visible as a raised line on the seed.
rhizome (rootstock)
(1) a subterranean stem (Fig. 2A).
(2) in the pteridophytes and seagrasses used in a broader sense to include prostrate creeping and short erect stems below the ground or shortly above it.
rhombo-cuneate
rhomboid in the upper part, cuneate below.
rhomboid (rhomboidal)
lozenge-shaped. Fig. 7G.
root
the descending axis of the plant, developed from the radicle and imbibing water and nourishment through its surface. Adventitious roots arise from stems, most often rhizomes or stolons.
rootstock
that part of an underground stem of a perennial from which the roots arise (e.g. a corm or often a rhizome).
rostellum
an extension of the upper edge of the stigma in orchids.
rostrate
beaked.
rosulate
leaves arranged in a radical rosette.
rotate
wheel-shaped, a corolla with very short tube and spreading limb . Fig. 12E.
rugose
wrinkled. Fig. 11F.
runcinate
a pinnatifid leaf with lobes pointing towards the base. Fig. 7H.
 
Fig. 14. A, longitudinal section through a regular flower with apocarpous gynoecium, numerous stamens and free petals and sepals (Ranunculus lappaceus); B, longitudinal section through a regular flower with an inferior ovary (epigynous perianth), fused perianth-segments and a staminal corona (Calostemma purpureum); C, longitudinal section through an irregular (zygomorphic) flower with a superior (hypogynous perianth) ovary of fused carpels and fused petals (Eremophila maculata); D, longitudinal section through a regular flower with a superior ovary (perigynous perianth) (Acaena sp.).
 
sagittate
arrow-shaped; applied to a leaf with two straight acute lobes at the base. Fig. 8F.
salverform
of perianths consisting of a narrow cylindrical tube topped by the spreading segments.
samara
a dry indehiscent fruit with a membranous wing at one end. Fig. 16A.
saprophyte
a plant obtaining its nutrient from dead organic matter.
scabridulous
minutely scabrous.
scabrous
rough to touch, usually on account of minute stiff, sometimes almost microscopic hairs or bristles.
scalariform
patterned like the rungs of a ladder.
scale
(1) a reduced leaf.
(2) usually used for one of many small flat organs.
scape
a radical leafless flowerstalk.
scarious
almost the same as membranous, but rather stiffer.
scattered
when leaves are irregularly arranged round the stem.
sclereid
a strongly thickened (lignified) cell, also called a stone-cell.
scorpioid cyme
a monochasium branching in a spiral or in more than one rank (cf. helicoid). Fig. 13F.
scurfy
covered with minute loose scales.
sectile
subdivided into small parts, as the pollen-masses of some orchids.
seed
a ripened ovule, consisting usually of two coats, within which is the embryo, with or without albumen.
segment
(1) each division of a pinnatisect leaf which reaches nearly or quite to the midrib, but is not separable without tearing.
(2) each division of a perianth reaching to the base.
sensu lato (s.l.)
in the broad sense; used of a name being used for a group which may alternatively be treated as two or more smaller groups.
sensu stricto (s.s.)
in the narrow sense; used of a name being used for a group which may alternatively be used for a larger group encorporating one or more other groups.
sepal
one of the divisions of the calyx.
septal placenta
when the placentas of a 2-celled ovary are attached to the partitions (septa, singular septum).
septate
divided by septa or partitions.
septicidal
when a capsule splits open through the dissepiments and the component carpels fall away separately. Zygophyllum aurantiacum, Dodonaea bursariifolia, Euphorbia. Fig. 16B.
septifragal
when the dissepiments remain attached to the axis of the capsule, but break away from the edges of the valves. Dodonaea viscosa, Datura stramonium.
septum
the membranous partition separating the two valves of the pod of Brassicaceae. See dissepiment.
serrate
toothed like a saw. Fig. 10J.
serrulate
when the teeth are very small.
sessile
without' any stalk; e.g. sessile glands. Fig. 11G.
seta (plural setae)
a bristle or stiff hair.
setaceous
bristle-like. When used to describe narrow leaf blades, it has the same meaning as subulate.
sigmoid
shaped like the letter S.
silicula
similar to a siliqua but the length less than three times the width.
siliqua
a dry fruit composed of two carpels separated by a partition (Cruciferae) with the length, excluding the beak, at least three times the width.
simple
(1) when a leaf is not divided into leaflets, the opposite of compound, although a simple leaf may be entire, toothed, or lobed.
(2) of a flower or perianth: having the segments or lobes in one whorl or cycle.
(3) of other organs: not lobed, branched, divided, or compound; a simple panicle has the branches undivided.
sinuate
leaf or other organ whose edge consists of shallow irregular lobes or teeth, with rounded spaces, called sinuses, between them. Fig. 10K.
sinus
the recess between two lobes or segments.
slow-creeping
in ferns a rhizome which elongates slowly so that the fronds are usually clustered.
sorus
a cluster of sporangia.
spathe
(1) two or more bracts enclosing the flowers of Iridaceae.
(2) a large bract enclosing the succulent flowerspike (spadix) of the arum and palm families.
spathulate
a leaf broad towards the summit, narrowed lower down. Fig. 7I.
species
a division of a genus, each species (group of individual plants) possessing characters which distinguish it from other species of the same genus. Each species bears two names, e.g., Eucalyptus obliqua, the first being the generic name, the second the specific one.
spicate
arranged in a spike.
spike
an undivided floral axis (rhachis, peduncle) bearing sessile flowers. Fig. 13B.
spikelet
a small spike bearing one or several flowers, occurring chiefly in the grass family.
spine (thorn)
a sharp point proceeding from the stem or other organ and not detachable without tearing.
spinescent
ending in a sharp point.
spinule
a small spine.
sporocarp
a thick-walled woody body containing sporangia.
sporophyte
a plant which bears no sexual organs but only asexual spores (for example the fern plant and, despite appearances, spermatophytes in which the gametophytes which produce the sexual structures are microscopic).
spreading
standing out horizontally, for example of branches; or standing out at right angles to the axis, for example of leaves or hairs.
squamule
a small scale within the sheathing base of the leaf, found in most submerged aquatic plants.
stamen
male organ of the flower, consisting of a short or long stalk (sometimes wanting) called the filament, which supports the anther. The latter consists of one or two pouches, or cells, containing the minute pollen-grains, by means of which the pistil is fertilised. Figs 15G­I.
staminodium (staminode)
an abortive or rudimentary stamen.
standard
the large posterior petal of Papilionoideae (Fabaceae).
stellate hairs
hairs with branches radiating like a star. Fig. 11H.
stem-clasping (amplexicaul)
when the base of a sessile leaf clasps the stem.
stigma
a point or small head at the summit of the style; or the stigmas may occupy the inner face of the style branches (Asteraceae) or the spreading hairs of the styles (Poaceae). Where there is no style, the stigma is sessile on the ovary. It is sticky and papillose and receives the pollen from the anthers.
stigmatic plate
the front part of the column in certain genera of orchids, bearing the female elements, and composed of a pedicel (or expanded style), carrying a vertical plate on the face of which are the stigma, the rostellum, and the viscid disk.
stipe
in ferns, the stalk of the frond.
stipellae (stipels)
two small secondary stipules sometimes found at the base of leaflets.
stipe
a small stalk, especially one rising above the insertion of the perianth and supporting a fruit, when it is the equivalent of a small gynophore; also applied to the stalks of scales and bracts.
stipitate
stalked, born on a stipe.
stipules
two often small appendages growing at the base of the leaf-stalk; they may be free from or attached to the leaf.
stolon (runner, sucker)
a basal branch growing just above or just below the surface, rooting at intervals and producing new plants. Fig. 2B.
stomate
microscopic pores in the outermost layer of cells, with a pair of reniform cells usually surrounding the aperture.
stramineous
straw-coloured.
striate
marked with parallel longitudinal lines.
strigose
with sharp stiff hairs usually appressed to the surface.
strobilus
a cone containing reproductive structures, as in some pteridophytes and conifers.
style
the narrow upper part of the carpel or pistil; it surmounts the ovary and supports the stigma, but is sometimes wanting.
sub-
a prefix meaning (1) somewhat, almost, as in suberect, subglobular; (2) under, inferior, as in subfamily.
subspecies
one level of subdivision of a species. A subspecies is a subdivision between the levels of species and variety.
subulate
awl-shaped. When applied to a leaf blade it means slender, rather stiff, often orbicular in cross-section owing to the incurved or involute margins. Fig. 12F.
sulcate
furrowed.
superficial
on the surface.
superior
an ovary is superior or free when the calyx, corolla and stamens are inserted below it on the floral axis, or when the hollow torus or receptacle is not united with it. In the first case the calyx, corolla, and stamens are hypogynous or inferior and in the second case they are inserted on or near the margin of the hollow torus and so become perigynous. A superior radicle points towards the summit of the fruit, and a superior (epitropous) micropyle points to the summit of the ovary.
superposed
inserted one above the other.
suture
the dorsal suture of a carpel (carpellary leaf or fruit-leaf) represents the midrib of the leaf; it is the outer (anterior) suture or seam. The ventral suture is on the inner side of the carpel and indicates the line where the edges of the folded leaf have become united; it bears the placenta and ovules, dehiscence may take place through one or both sutures.
sympatric
with more or less the same geographical distribution.
sympetalous
a corolla in which the petals are united by their edges into a cup or tube . Less correctly called gamopetalous or monopetalous.
syncarpous
an ovary, pistil, or fruit composed of two or more united carpels.
 
Fig. 15. A, imbricate aestivation; B, contorted aestivation; C, valvate aestivation; D, transverse section through an ovary with axile placentation (Eremophila maculata); E, transverse section through an ovary with parietal placentation (Villarsia umbricola); F, longitudinal and transverse sections through an ovary with free central placentation (Samolus repens); G, a basifixed anther with longitudinal dehiscence (Wilsonia rotundifolia); H, a 2-celled dorsifixed anther with longitudinal dehiscence (Amaryllis belladonna); I, an anther dehiscing by apical pores (Solanum capsiciforme).
 
taxon
any group or rank in a biological classification, e.g. family, subfamily, genus, species, subspecies, variety.
tendril
a filiform organ by which climbing plants cling to some object within reach.
terete
slender-cylindrical, but not so slender as filiform. Fig. 12G.
ternate
arranged in or divided into threes.
testa
the outer seed-coat.
tetrad
a group of four.
thyrse
an inflorescence in which the primary axis is racemose and the secondary axes cymose.
tomentose
densely covered with short soft matted hairs (tomentum). Fig. 11I.
toothed (dentate)
notched so as to resemble a row of sharp teeth.
torus
see receptacle (1).
tree
a vague term usually used for woody plants above about 3 m high with a single trunk or rarely several trunks and most branching usually in the upper part.
triad
a group of three.
trichome
a usually unbranched epidermal outgrowth, e.g. hairs and papillae.
trichotomous
of a stem or branches divided into three, once or several times.
trifid (3-fid)
cut about half-way into three parts.
trifoliate
having three leaves.
trifoliolate
a leaf of three leaflets.
trigonous
a stem or other organ which is triangular when cut transversely. Fig. 12H.
trimerous
in threes.
tripartite
divided into three parts nearly to the base.
tripinnatisect
thrice pinnatisect.
triquetrous
a triangular stem or other organ when the angles are sharp. Fig. 12I.
trisect
cut into three segments to the base of the midrib.
trullate
ovate but 4-angled like a brick-layer's trowel.
truncate
cut off squarely. Figs 8I & 9H.
tuber
(1) a swollen branch of an underground stem, producing buds, as the potato (Fig. 2D).
(2) a swollen part of a root, acting as a reservoir of nourishment (Fig. 2C).
tubercle
a small wart-like protuberance. For tubercle-based hairs, see Fig. 11J.
tuberculate
covered with tubercles.
tunic
the outer covering of some bulbs and corms.
turbinate
top-shaped.
turgid
swollen.
turion
starch-filled perennating organ of Ruppia.
 
Fig. 16. A, samaras (Atalaya hemiglauca); B, a septicidal capsule (Burchardia umbellata); C, a loculicidal capsule (Hannafordia bissellii); D, a cicumscissile capsule (Portulaca oleracea); E, an achene (Clematis microphylla); F, an Asteraceae achene surmounted by a pappus (Senecio odoratus); G, a poricidal capsule (Papaver setigerum); H, a berry (Solanum centrale); I, a drupe cut through the epicarp and mesocarp to reveal a portion of the hard endocarp (Olea europaea): J, a follicle (Brachychiton gregorii).
 
ultimate segment
final division of a leaf; in ferns it may be a pinnule or part of a pinnule if the segment is deeply lobed.
umbel
inflorescence where the divergent branches or rays start from the same point. In a simple umbel each ray bears one flower. Fig. 13G.
umbellule
a partial umbel borne at the summit of each ray of a compound umbel.
umbilicate
with a conspicuous depression in the centre.
umbonate
bearing a small boss or elevation in the centre.
uncinate
with a hook at the apex. Fig. 9G.
undershrub
a very low growing shrub.
undulate (crisped)
wavy on the edges. Fig. 10L.
unilateral
one-sided.
unisexual
a flower of one sex, either male or female.
urceolate
urn-shaped. Fig. 12J.
utricle
a small bladder; a membranous bladder-like sac enclosing an ovary or fruit.
 
vaginate
sheathed.
valvate
petals and sepals whose edges, in bud, meet without overlapping. Fig. 15C.
valve
one of the pieces formed by the vertical splitting of the pericarp of certain fruits when ripe. The valves usually consist of the backs of the carpels.
variety
one level of subdivision of a species. See subspecies.
vascular bundles
long tubes or fibres which establish communication between the various parts of a plant. An open vascular bundle is one divided by a layer of cambium, so that the bundle is capable of constant growth; a closed bundle (as in vascular cryptogams and monocotyledons) has no cambium and cannot increase in size.
vascular commissure
vascular connection of vein endings.
velum
a membranous veil.
ventral
see suture.
vernation
the manner in which unexpanded leaves are arranged in the leaf bud.
versatile
when the anther is lightly attached by some point of its back to the filament, so as to swing easily.
verticillate
see whorled.
vesicular
of hairs which are bladder-like.
villous
beset with long soft hairs.
virgate
with many long slender ascending almost parallel branches. Fig. 1C.
vitta
linear longitudinal vessel in the fruit of some Apiaceae.
viviparous
see proliferous.
 
whorl (verticil)
a set of organs, proceeding from the same node, and arranged in a circle around the axis. Fig. 3E.
whorled (verticillate)
arranged in a whorl.
wing
(1) any kind of flat membranous expansion.
(2) one of the two lateral petals of papilionate flowers .
woolly
similar to tomentose but the hairs curlier. Fig. 11K.
 
zygomorphic
see irregular.