Glossary of Botanical Terms - C

C

caducous

falling off early, for example the sepals of poppies, that fall off when the petals begin to open; compare persistent.

caespitose

tufted; e.g. the growth form of some grasses.

callus

(plural calli) generally, a protruding mass of tissue; in orchids, fleshy outgrowths from the labellum which can be variously shaped from papillae to plates; in grasses, hardened extension from the base of a floret (formed from the rachilla joint and/or the base of the lemma) which may or may not elongate and is often covered in hairs or bristles.

calycophyll

a leaf-like structure formed from a sepal or calyx lobe which enlarges, usually many-fold, before or after anthesis, especially when most of the sepals or calyx lobes retain their original size. More extreme than an accrescent calyx, calycophylls are found in Rubiaceae. cf. semaphyll, pterophyll.

calyculate

having an epicalyx.

calyculus

(1) a cup-shaped structure formed from bracts, (2) in some Asteraceae, a circle of bracts below the involucre.

calyptra

a hood or lid; see operculum.

calyx

(plural calyces) the outer whorl of a flower, usually green; the sepals of one flower collectively.

calyx tube

a tube formed by the fusion of the sepals (calyx), at least at the base.

campanulate

bell-shaped.

campylotropous

when the ovule is oriented transversely (i.e. with its axis at right angles to its stalk) and with a curved embyro sac; cf. amphitropous, anatropous, orthotropous.

canaliculate

channelled; with a longitudinal groove.

canopy

the branches and foliage of a tree; crown; cf. trunk.

capillary

1. (noun) a tube, pore or passage with a narrow internal cross-section.

2. (adjective) slender, hair-like.

capitate

with knob-like head; of an inflorescence, with the flowers unstalked and aggregated into a dense cluster; of a stigma, like the head of a pin.

capitulum

a dense cluster of sessile, or almost sessile, flowers or florets; a head.

capsule

a dry fruit formed from two of more united carpels and dehiscing when ripe (usually by splitting into pieces or opening at summit by teeth or pores).

carina

(adjective carinate) see keel.

carpel

a female organ borne at the centre of a flower, consisting of an ovary, a style and a stigma. The gynoecium is the collective term for all the carpels of a single flower.

cartilaginous

hard and tough; gristly.

caryopsis

a dry, indehiscent, one-seeded fruit in which the seed coat is closely fused to the fruit wall, as in most grasses.

casual alien

a plant that appears with no apparent human assistance but does not develop a sustained population(s). Plants that persist only by new introductions; cf. alien.

cataphyll

Early leaf forms of plants or shoots, such as cotyledons, bud-scales, rhizome-scales; anatomically they are leaves, but do not develop to perform the usual functions of photosynthetic leaves.

catkin

a spike, usually pendulous, in which the mostly small flowers are unisexual and without a conspicuous perianth; e.g. willows, poplars, oaks and casuarinas. The individual flowers often have scaly bracts; they are generally wind-pollinated. The catkins are usually shed as a unit.

caudate

having a narrow tail-like appendage.

cauline

borne on an aerial stem, e.g. leaves, flower or fruits (when applied to the latter two organs, usually referring to older stems; = cauliflorous).

cell

1. basic (microscopic) unit of plant structure, generally consisting of compartments in a viscous fluid surrounded by a wall.

2. cavity of an anther or ovary.

centrifixed

of a two-branched organ attached by its centre, e.g. a hair, or anther.

chartaceous

with a papery texture.

chamber

cavity of an ovary.

chasmogamous

of flowers that are pollinated when the perianth is open; cf. cleistogamous.

chimera

an individual composed of two or more genetically different tissues, most commonly as a result of a graft and sometimes within the individual, by mutations and irregularities that occur during cell division.

chiropterophilous

pollinated by bats.

chlorophyll

a green pigment in chloroplasts, essential for photosynthesis.

chloroplast

an organelle present in plant cells that contains chlorophyll.

cilia

(singular cilium, adjective ciliate) generally, hairs more or less confined to the margins of an organ, like eye-lashes; in motile cells, minute, hair-like protrusions which aid motility.

circinate (circinnate)

spirally coiled with the tip innermost; e.g. the developing fronds of most ferns.

cladode

a photosynthetic stem, often leaf-like and usually with foliage leaves either absent or much reduced; cf. phyllode.

class

the principal category for taxa in a rank between division and order.

clathrate

latticed or pierced with apertures. In this structures, such as scales, this appearance is caused by thick cell walls between adjacent cells and thin cell walls on the sides of the cells that face the surfaces of the scale.

clavate

club-shaped.

claw

1. narrow, stalk-like basal portion of petal, sepal of bract.

2. in Melaleuca, the united portion of a stamen bundle.

cleistogamous

of flowers that self-pollinate and never open fully, or self-pollinate before opening; cf. chasmogamous.

climber

a plant growing more or less erect by leaning or twining on another structure for support.

cline

(adjective clinal) continuous morphological variation in form within a species or sometimes between two species.

clone

plants derived from the vegetative reproduction of an individual, all having the same genetic constitution.

coalescent

plant parts fused or grown together to form a single unit.

coherent

(of like parts) sticking together, but not firmly or solidly as in connate.

colleter

a multicellular, glandular hair that usually produces a mucilaginous substance and is located on sepals, stipules, or petioles, or on nearby parts of stems; commonly found on plants in the order Gentianales.

columella

in flowering plants, the central axis of the cone or fruit, e.g. in Callitris.

column

1. structure extending above ovary and incorporating the style and stamens; gynostemium; e.g. in orchids.

2. in grasses, the lower, stouter, and usually twisted part of an awn, distinct from the slender upper part or bristle.

columnar

shaped like a column.

commercial name

a name often of no botanical standing and not governed by the ICNCP. The term generally applies to names such as Trademark Names, names covered by Plant Breeders Rights, Patents and Promotional Names; often used to enhance the sale of a plant.

commissure

the seam or face by which two carpels adhere.

community

an assemblage, in nature, of plants that characteristically occur together.

compound

composed of several parts, for instance a leaf with leaflets, a gynoecium with several carpels, or an inflorescence made up of smaller inflorescences.

compressed

flattened lengthwise, either laterally (from side to side) or dorsally (from front to back).

concolorous

the same colour throughout.

cone

a fruit, usually woody, ovoid to globular, including scales, bracts or bracteoles arranged around a central axis, e.g. in gymnosperms, especially conifers and Casuarina.

conflorescence

of an inflorescence when the overall structure substantially differs from that of the individual branches of the inflorescence, a rarely used term; e.g. the bottlebrush multiple-flower head of callistemons.

connate

fused to another organ (or organs) of the same kind; e.g. petals in a floral tube; cf. adnate.

connective

the part of an anther that connects the anther cells.

connivent

coming into contact or converging.

conspecific

belonging to the same species.

contiguous

adjoining, touching, but not united.

contorted

twisted out of the normal shape.

convolute

referring to the arrangement of floral or foliar organs in a bud when each organ or segment has one edge overlapping the adjacent organ or segment; a form of imbricate arrangement; contorted.

cordate

heart-shaped, with the notch lowermost; of the base of a leaf, like the notched part of a heart.

coriaceous

leathery; stiff and tough, but somewhat flexible.

corm

fleshy, swollen stem base, usually underground, storing food reserves, with buds naked or covered by very thin scales; a type of rootstock. Adjectives derived from "corm" include "cormose" and "cormous".

corolla

collective term for the petals of a flower.

corona

(adjective: coronate) literally, crown

1. in flowering plants, ring of tissue arising from the corolla or perianth of a flower and standing between the perianth lobes and the stamens; e.g. the daffodil trumpet, passionfruit.

2. in grasses, a hardened ring of tissue surmounting the lemma in some species.

corymb

(adjective corymbose) inflorescence with branches arising at different points but reaching about the same height, giving the flower cluster a flat-topped appearance.

costa

(adjective costate) a rib.

costapalmate

a costapalmate leaf has a definite costa (midrib), unlike the typical palmate or fan leaf, but the leaflets are arranged radially like in a palmate leaf.

cotyledon

primary leaf or leaves of an embryo, becoming the seed leaf or leaves.

crenate

with blunt or rounded teeth, scalloped.

crenulate

minutely scalloped.

crisped

finely curled. A term generally applied to the edges of leaves and petals.

crown

see canopy.

cross

to make something interbreed; the act of hybridization.

cruciform

cross-shaped.

crustaceous

hard, thin and brittle.

cryptogams

ferns, bryophytes, algae and fungi (including lichenized fungi); 'lower plants'; plants producing spores, and without stamens, ovaries or seeds, literally plants whose sexual reproductive organs are not conspicuous cf. phanerogam.

cucullate

from Latin cucullus, a hood. Hood-like or hooded, commonly referring to the shape of leaves or petals. (Example: Pelargonium cucullatum). Similarly derived terms include cuculliform and cuccularis.

culm

in grasses, sedges, rushes, and some other monocotyledons, an aerial stem bearing the inflorescence; strictly, from the base of the plant to the lowest involucral bract (or base of the inflorescence).

cultigen

a plant whose origin or selection is primarily due to intentional human activity.

cultivar

the term cultivar is derived from cultivated variety and denotes an assemblage of cultivated plants clearly distinguished by one or more characters (morphological, physiological, cytological, chemical or other); when reproduced (sexually or asexually), the assemblage retains its distinguishing characters. A cultivar may arise in cultivation or be introduced from the wild. It is a variant of horticultural interest or value. Cultivar names are written with single quotation marks around them e.g. 'Blue Carpet', 'Alba'. All new names established after 1 January 1959, must be in common language (that is, not in Latin) but names established in Latin prior to this date are retained in Latin form.

cultivar epithet

the defining part of a name that denominates a cultivar. Cultivars are designated by fancy (q.v.) epithets appended either to the scientific name or to the common name of the taxon to which they belong; they are not italicized but placed in single quotation marks, for example Rubus nitidoides 'Merton Early'. 'Merton Early' is the cultivar epithet.

cuneate

wedge-shaped; with straight sides converging at base. See Leaf shape.

cuspidate

tipped with a cusp.

cutting

a piece of plant, usually an apical tip of shoot structure but may be root or leaf, cut from plant and used for vegetative propagation.

cyathium

an inflorescence of unisexual flowers surrounded by involucral bracts, e.g. the flowers of Euphorbia.

cyme

(adjective cymose) inflorescence in which the main axis and all lateral branches end in a flower (each lateral may be repeatedly branched).

cypsela

a dry, indehiscent, one-seeded fruit formed from an inferior ovary.