achene - see cypsela - commonly used to refer to the fruit in the Compositae but developmentally only referable to dry, one seeded mericarps found in the Gramineae (Poaceae).

alveolate - (referring to the receptacle) a receptacle with tall ridges with entire or variously divided margins surrounding the polygonal depressions (Small, 1919: 138).

anther collar - see filament collar

apical anther appendages - the sterile apical tissue above the anther thecae.

apical callus -referring to the distinctive apical rim beneath the pappus in some groups.

appendage - literally a part added to another, a term applied to anthers, style arms or phyllaries where the extension may differ in texture, colour or by a constriction at the end of the organ to which it is added.

areolate - (referring to the receptacle) a receptacle with 'polygonal depressions... more or less flat bottomed and surrounded by a low, narrow ridge' (Small, 1919: 138).

auriculate - possessing ear-like structures, such as those are the base of petioles, or the ear-like projection of the corona-like pappus in some members of the tribe Anthemideae.

awn - a stiff bristle-like pappus element.

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barbellate - usually referring to pappus setae where the length free cell ends are less than or equal to the diameter of the pappus setae.

basal anther appendages - referring to the basal sterile tissue of calcarate anthers.

basifixed - usually referring to anthers fixed to the filaments by their bases, e.g. in the subfamily Asteroideae, with all the pollen grains above the insertion point of the filament.

beak - see rostrum

bilabiate - usually referring to corollas with two distinct lobes, an outer often distinctly toothed and an inner lip also distinctly lobed, e.g. in many members of the tribe Mutisieae s.l. in which the outer lip is 3-lobed and the inner of 2 linear lobes.

bilabiate florets - florets possessing a corolla with 2 smaller inner lobes and a larger 3-lobed outer lip, common in the tribe Mutisieae.

bisexual - see hermaphrodite

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caducous - falling off prematurely or easily, eg. pappus setae, cf. deciduous.

calcarate - usually referring to stamens whose anthers have elongated sterile portions beneath the thecae and extending below the filament insertion point.

calyculus - a subinvolucral series of bracts, typically found in some genera of the tribe Senecioneae. In some genera the calyculus is often confused for the involucre since the calycular bracts are equal in length to the phyllaries; they are usually much shorter.

calycular bracts - the individual bracts making up the calyculus.

capillary - (sometimes capillaceous) referring to the fine, usually smooth pappus setae, e.g. in Reichardia (tribe Lactuceae), and commonly in members of the tribe Senecioneae.

capitulescence - simply another term for inflorescence, q.v. - the arrangement of capitula.

capitulum (pl. capitula) - the primary inflorescence found in the Compositae, often referred to as a flower by the layman when viewing a typical radiate capitulum, and often a head in many texts, and composed of an involucre of protective bracts around the receptacle (the phyllaries), surrounding the florets.

carpopodium - receptacular tissue (the attachment area) usually found at the base of the achene, although sometimes absent, and sometimes highly diagnostic in its shape and cellular form in some taxa (e.g. tribe Eupatorieae). The tissue can be procurrent on the base of the achene body or ribs, sometimes distinctly shaped (commonly cylindrical, annular or stopper-shaped), usually multi-layered, the cells rarely ornamented with hairs or glands.

caudate - anthers possessing sterile tails at the base of the thecae.

cleistogamous - typically a flower that never opens but self-pollinates within the closed corolla; in Compositae this is taken as a capitulum that never opens, such as in the autumnal capitula found in Chaptalia, Leibnitzia, Uechtritzia (tribe Mutisieae).

conduplicate - an organ folded together lengthways, such as a palea enveloping a disc floret.

corolla lobes - the individual lobes of a corolla each corresponding to a fused petal.

corolla throat - the often dilated portion of the corolla above the corolla tube.

corolla tube - the basal part of the corolla from above the achene to the corolla throat.

corymbophore - (Lundgren, 1972) = the peduncle or an inflorescence, or as Freire (1993) preferred, a capitulescence, which was leafless.

cypsela - often considered the alternative to achene, but actually the correct term for the fruit in the Compositae - a usually dry, indehiscent, bicarpellate, unilocular, one-seeded fruit developing from an inferior ovary and surrounded by other floral tissue.

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deciduous - falling off with maturity or shed seasonally, e.g. achenes, leaves.

dioecious - with male and female capitula borne on separate plants, e.g. Baccharis (tribe Astereae), Gochnatia spp. (tribe Mutisieae), some members of the tribe Inuleae s.l., thus maximizing obligatory cross-fertilization.

disc florets - florets occupying the central disc of a capitulum and often hermaphrodite with actinomorphic tubular corollas, although such florets may be male-fertile as well as female-fertile producing both pollen and fruits, or they may be male-fertile and female-sterile producing pollen and no fruits.

disciform - type of heterogamous capitulum which resembles a discoid capitulum but when the marginal, or outer, florets are different from those of the disc or central florets, but are still eradiate.

discoid - type of capitulum when all florets are tubular or filiform and the capitulum lacks any different marginal florets; florets may be all male, all female or all hermaphrodite.

distant - the opposite of imbricate (cf. Stearn, 1966), where phyllaries do not overlap but are clearly in more than one series, sometimes incorrectly referred to as 'eximbricate' (cf. King & Robinson, 1987 - in the tribe Eupatorieae).

dorsifixed - usually referring to the anthers which are attached to the filaments by their upper surface, e.g. in the subfamily Cichorioideae, whose anther thecae are calcarate and caudate, i.e. with pollen grains below the point of attachment of the anthers to the filaments, cf. basifixed.

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ecalcarate -lacking prolongations of anther thecae below the filament insertion point.

ecalyculate - lacking a calyculus.

ecaudate - lacking sterile tails below the anther thecae.

ecoronate - lacking a corona.

eplaeaceous - lacking paleae.

epappose - lacking a pappus.

erosrate - lacking a rostrum.

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filament collar - a region of often thick-walled and differently shaped cells below the anther, often recognizable as a swollen, or flattened area at the apex of the filament. In some groups it may be indistinct, e.g. tribe Mutisieae.

filiform - thread-like, typically used to refer to the corollas of female florets lacking an anther cylinder, where the corolla closely envelops the style, i.e. in the tribe Inuleae, female capitula in Baccharis (tribe Astereae).

fimbriate - margins fringed, often with hairs, e.g. the fovea on the receptacle in Compositae.

fimbrillate - (referring to the receptacle) a receptacle with the polygonal depressions surrounded by high, laciniate, lacerate, or denticular ridges cut up into a number of paleaceous-like structures (Small, 1919: 138).

floret - the diminutive individual flowers typically found in the Compositae.

fovea - pits, typically in the receptacle in Compositae.

foveolate - (referring to the receptacle) a receptacle covered with 'shallow circular or polygonal depressions, each with a small vascular protuberance...' (Small, 1919: 138).

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glomerule - strictly an indeterminate dense cluster of sessile or subsessile flowers, but in the Compositae it refers to a condensed fascicle of capitula, typically on the terminal branches of an inflorescences, but lacking a distinct secondary receptacle and involucre, cf. synflorescence (or syncalathium), eg. Eremanthus (tribe Vernonieae), Gochnatia spp. (tribe Mutisieae)

glomerulescence - the whole flowering structure made up of glomerules.

gynodioecious - the condition in which hermaphrodite florets occur on an otherwise female plant.

gynomonoecious - the condition in which female florets occur on an otherwise

hermaphrodite plant.

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head - see capitulum

hermaphrodite (sometimes referred to as bisexual) - florets possessing both an anther cylinder and style, usually both fertile although in some taxa florets may be functionally male or female.

heterogamous - referring to capitula when florets are of two sexual states and include radiate, radiant, disciform and bilabiate (common in the tribe Mutisieae e.g. Uechtritzia with outer florets with staminodes) capitula.

heteromorphic - usually referring to achenes in a capitulum which are of different shapes/forms, or to different series of pappus setae which differ in form.

homogamous - referring to capitula when all florets are of one sexual state, all male, all female or all hermaphrodite.

homomorphic - usually referring to achenes in a capitulum which are all similar.

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imbricate - a condition in which the parts are overlapping like tiles on a roof or scales on a fish; in the Compositae it is often used to describe the phyllaries in the involucre.

inflorescence - since the primary inflorescence in the Compositae is a capitulum, often viewed as a flower, the term inflorescence (or general inflorescence, sensu Davis & Grierson, 1975: 7) is here reserved for the whole flowering structure, even if that constitutes the whole plant in some annuals.

infructescence - a confusing term often used for the fruiting structure derived from an inflorescence.

involucral bracts - see phyllaries

involucre - the protective row or rows of bracts surround the florets and receptacle in the capitulum.

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ligulate - in Compositae it refers to either a floret type or capitulum type where the corollas are modified into a flat, strap-shaped limb with 5 apical teeth, often with a short or absent corolla tube at the base. Such florets may be hermaphrodite or female. Typically in the tribe Lactuceae all florets are identical and ligulate, just different in size and maturity across the capitulum, also present in Catamixis (tribe Mutisieae).

ligule - in Compositae it is used with reference to the flat, strap-shaped limb, with 5 apical teeth, of the corolla in a ligulate capitulum, e.g. members of the tribe Lactuceae.

limb - the extended portion of a corolla such as that found in a ray florets, but also applied to the portion of the corolla above an often obvious corolla tube.

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marginal florets - the single or multiple series of florets around the edge of a capitulum and surrounding the central or disc florets, and which may be ray, filiform, or radiant florets, etc.

monoecious - typically having separate male and female flowers on the same plant, eg. Ambrosia, Xanthium (tribe Heliantheae).

myxogenic - usually referring to the hairs, often found on achenes, that swell producing mucilage upon contact with water, i.e. members of the tribe Inuleae s.l.

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paleaceous - palea-like, sometimes referred to as chaffy; when referring to the receptacle the receptacle is covered with membranous scales, each subtending a floret.

paleae (paleaceous, epaleaceous) - usually interpreted as rudimentary bracts subtending individual florets, or sometimes as phyllaries interspersed amongst the florets.

pappus - usually considered to be the remnant of the calyx on top of the achene/cypsela, and can be present either as capillary setae, coarse bristles, awns, paleaceous or simply present as an erose or laciniate crown.

pedicel - strictly referable to the stalk of an individual flower, or floret, such as may be found in many species of Cotula (tribe Anthemideae), this term is more usually applied to the stalk of individual capitula in situations where plants bear several capitula in their inflorescences.

peduncle - the main stipe to the whole inflorescence, although often used for the individual capitulum stalk, cf. pedicel.

phyllary (pl. phyllaries) - the involucral bracts surrounding the receptacle in the capitulum, usually offering some protection to the buds and eventually developing achenes/cypselas, sometimes becoming patent or recurved at achene maturity or dispersal, sometimes aiding dispersal (as a phyllary-achene complex, e.g. Parthenium - tribe Heliantheae), rarely completely dehiscent (Chromolaena - tribe Eupatorieae, Piptocarpha - tribe Vernonieae), and very rarely involving, or enveloping, the achenes and becoming ornamented (e.g. Acanthospermum, Melampodium, Xanthium - tribe Heliantheae).

plumose - (in Compositae) referring to pappus setae where the free cell ends at least 3 ´ or more in length than the diameter of the seta rachis.

pseudobilabiate florets - referring to florets whose corollas possess a single adaxial lobe and an outer 4-lobed limb, e.g. in the subfamily Barnadesioideae.

pseudocephalium - aggregations of capitula into secondary capitulum-like head (Davis & Grierson, 1975: 1) - referring to compound heads found in Echinops (tribe Cardueae), Gundelia (recently placed in the tribe Gundelieae), etc., although Davis & Gierson (1975: 7) also called these heads.

pseudoglomerule - applied by Katinas (1996) etc., to forms of inflorescence where individual inflorescence branches terminate in glomerules, strictly referring to the branching pattern of the inflorescence counting each glomerule as a capitulum and deriving the branching pattern of the whole, hence pseudocorymb, pseudoraceme and pseudospike. However Katinas also applied the same 'pseudo-' terminology to basic corymbs etc. with each branch/let terminating in a solitary capitulum!

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radiant - typically referring to capitula in which the outer marginal florets are enlarged, sometimes with zygomorphic corollas, and sterile, and possessing central tubular hermaphrodite florets.

radiate - type of capitulum possessing marginal florets with a distinct ray limb, this may be 1 to four toothed, and a central disc of often tubular hermaphrodite florets.

ray florets - referring to florets whose corolla usually possesses a limb with 4 or fewer lobes, the true ray possessing 3 lobes. Ray florets are marginal florets and may be in one or more series, and be female fertile, female sterile (possessing a non-receptive style) or neuter (lacking both stamens and style).

receptacle - (in Compositae) the tissue in the capitulum upon which the florets are found, which may be concave, flat or variously convex (to conical or even approaching cylindrical), variously ornamented or pubescent, possess receptacular bracts, or paleae.

rostrum - referring to the apical beak or extension of the achene/cypsela which is surmounted by the pappus - e.g. Taraxacum, Tragopogon (tribe Lactuceae).

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scabrid or scabrous - with reference to pappus setae where the free projecting cell ends can be seen with a hand lens.

scape - flowering stem of a plant whose leaves are all radical, bearing a terminal capitulum. Sometimes also defined as possessing 'only basal foliage leaves and one or more capitula' as well as 'sometimes possessing bracts (or reduced scale leaves)' on the scape.

scapiform - resembling a scape.

scrobiculate - (referring to the receptacle), described by Small (1919: 138) as a receptacle covered with 'low mounds of tissue with furrows between, the top of each mound being occupied by the remains of the vascular bundle,...'.

seta (pl. setae) - literally a bristle, or bristle-like organ, here an individual element of the pappus.

setiferous - (referring to the receptacle) a receptacle whose polygonal depressions are surrounded by high laciniate ridges with the laciniae of the margins long and narrow, like paleaceous pappus setae (Small, 1919: 138).

setulae - the small hairs usually found on achenes/cypselas and typically twin hairs.

setuliferous - possessing short, stiff hairs, such as the twin hairs on the body of an achene/cypsela.

squamellum (pl. squamellae) - a broadened bristle or scale-like unit of the pappus

stereome - a central sclerified portion of a phyllary that may be undivided or divided into two, e.g. in members of the tribe Inuleae s.l. (Gnaphalieae).

stigmatic areas - areas of the style arms/branches covered with stigmatic papillae, present as areas covering the inside of the style arms/branches or separated into two marginal bands which sometimes fuse towards the apex of the style arms/branches.

style arm appendages - prolongations of the style arms/branches, beyond the stigmatic areas.

style arms (alt. style branches) - the upper divisions of the style into two arms or branches that, in fertile style arms, bear the receptive stigmatic papillae.

stylopodium - a more or less well developed nectary on top of which the style is situated

subimbricate - possessing phyllaries in that are progressively towards the inner series but not evenly overlapping or longer inwards.

subinvolucral bract/s - individual bracts surrounding or below an involucre, sometimes only subtending individual pedicels, e.g. in Mikania (tribe Eupatorieae).

subplumose - when referring to pappus setae where the free cell ends are between 2 and 3 ´ the diameter of the seta rachis. [This is more distinctive than coarsely barbellate, but less than plumose].

subradiate - a heterogamous capitulum with the outer florets bearing rays not exceeding the phyllaries.

subshrub (syn. suffrutex) - plants with an often woody, sometimes fleshy, underground perennating organ and annual flowering stems, often in an adaptation to perennate the plants through periods of drought or through fire.

suffrutex - see subshrub

syncalathium (pl. syncalathia; syn. synflorescence) - literally united calathia, as found in the Compositae with secondarily compound inflorescences. A rarely used term, although technically appropriate.

synflorescence - an aggregation of individual capitula onto a secondary receptacle and surrounded by a secondary involucre, e.g. Lagascea (tribe Heliantheae), Elephantopus (tribe Vernonieae), Sphaeranthus (tribe Inuleae). See syncalathium.

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tubular - typically referring to a corolla of a hermaphrodite floret that envelops an anther cylinder and style, compared with a filiform corolla of a female floret which just envelops a style.

twin hair/s - the translation of the German zwillingshaare (Hess, 1938), sometimes referred to as duplex hair/s.

umbo - literally diskus or mamilla, an abruptly raised conical, grooved or depressed, generally waxy structure within the pappus at the achene apex, e.g. in Tyrimnus, Jurinea (tribe Cardueae).

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umbonate - (adj.) possessing an umbo.

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vallecular canal - usually a resin canal opposite a longitudinal sulcus.

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xylopodium - a woody subterranean, sometimes slightly fleshy, derived from the roots.

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Davis, P.H. & A.J.C. Grierson. (1975). Compositae. In: P.H. Davis (ed.), Flora of Turkey. Edinburgh University Press. vol. 5.

Freire, S.E. (1986). Revisíon del géneo Lucilia (Compositae, Inuleae). Darwiniana 27: 431-490.

Hess, R. (1938). Vergleichende Untersuchungen über die Zwillingshaare der Compositen. Bot. Jahrb. Syst. 68: 435-496.

Katinas, L. (1996). Revísion de las especies Sudamericanas del género Trixis (Asteraceae, Mutisieae). Darwiniana 34(1-4): 27-108.

King, R. M. & H. Robinson (1987). The genera of the Eupatorieae (Asteraceae). Monogr. Syst. Bot. 22.

Lundgren, J. (1972). Revision of the genus Anaxeton Gaertn. (Compositae). Opera Bot. 31: 1-59.

Small, J. (1919). The origin and development of the Compositae. New Phytologist 18 (Reprint 11): 1-334 + plates 1-6.

Stearn, W.T. (1966). Botanical Latin - History, grammar, syntax, terminology and vocabulary. David & Charles, Newton Abbot.