The families of flowering plants
~ Former Liliaceae, combining Amaryllidaceae-Agapanthoideae and -Allioideae with Asparagaceae-Brodiaeoideae of APG III
Including Agapanthaceae Lotsy, Gilliesiaceae Lindley, Milulaceae Traub, Themideae (Themidaceae) Salisb., Tulbaghiaceae Salisb.
Habit and leaf form. Herbs; laticiferous (mucilaginous, e.g. in Allium), or non-laticiferous and without coloured juice; bearing essential oils, or without essential oils. Normal plants. Perennial; with a basal aggregation of leaves (but sometimes the leaves long-sheathed so as to appear cauline); bulbaceous, or cormous (especially Themidaceae), or rhizomatous (rarely e.g. Agapanthus). Mesophytic, or xerophytic. Leaves not evergreen; alternate; conspicuously distichous (e.g. leek), or spiral; flat, or rolled, or terete (or angular); sessile (usually), or petiolate (rarely, e.g. Allium ursinum); sheathing. Leaf sheaths with free margins. Leaves aromatic (often onion-scented, with allylic sulphides), or without marked odour; simple; epulvinate. Lamina entire; linear, or lanceolate, or ovate (rarely); parallel-veined, or palmately veined, or pinnately veined (then pinnate-parallel); without cross-venules.
General anatomy. Plants with laticifers (articulated), or without laticifers. The laticifers of Allium, in leaves (in the inner chlorenchyma).
Leaf anatomy. Stomata present; anomocytic.
The mesophyll containing calcium oxalate crystals, or without calcium oxalate crystals (? raphides sometimes present, sometimes absent). Minor leaf veins without phloem transfer cells (Allium, Triteleia).
Stem anatomy. Secondary thickening absent. Xylem without vessels. Sieve-tube plastids P-type; type II.
Root anatomy. Root xylem with vessels; vessel end-walls scalariform and simple (mainly simple, by contrast with Amaryllidaceae).
Reproductive type, pollination. Plants hermaphrodite. Floral nectaries present. Nectar secretion from the gynoecium (from septal nectaries). Pollination entomophilous.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in inflorescences (usually), or solitary (Ipheion); in umbels. The ultimate inflorescence unit cymose. Inflorescences scapiflorous; umbellate, usually representing one or more contracted, helicoid cymes; with involucral bracts (the umbel surrounded by (1)2(to several) bracts, which may be fused); spatheate (with reference to the one to several spathal involucral bracts). Flowers fragrant, or odourless; regular to somewhat irregular. The floral irregularity e.g. in some Allium species, involving the androecium. Flowers 3 merous; cyclic; pentacyclic. Perigone tube present, or absent.
Perianth of tepals; 6; free to joined; 2 whorled (3+3); isomerous; petaloid; similar in the two whorls; white, or violet, or blue, or purple, or yellow, or green and white, or brown and white, or white and red.
Androecium 6. Androecial members adnate (at the base of the tepals, or to the tube); all equal (mostly), or markedly unequal (Ipheion); free of one another (mostly), or coherent (the filaments sometimes basally cohering in Allium); 2 whorled (3+3). Androecium exclusively of fertile stamens (usually), or including staminodes. Staminodes when present, 3, or 4. Stamens 6 (usually), or 2–3 (e.g. the Gilliesia group, Leucocoryne); isomerous with the perianth (usually), or reduced in number relative to the adjacent perianth; alterniperianthial, or oppositiperianthial (sometimes even when six-stamened e.g. see Dahlgren et al. 1985, drawings of Tritagma, p. 197); filantherous (the filaments flat). Filaments appendiculate, or not appendiculate. Anthers dorsifixed; dehiscing via longitudinal slits; introrse. Endothecium developing fibrous thickenings. The endothecial thickenings spiral. Microsporogenesis successive. Tapetum glandular. Pollen grains aperturate; 1 aperturate; sulcate; 2-celled.
Gynoecium 3 carpelled. Carpels isomerous with the perianth. The pistil 3 celled. Gynoecium syncarpous; synstylovarious, or eu-syncarpous; superior. Ovary 3 locular. Gynoecium stylate. Styles 1; almost gynobasic, or apical. Stylar canal absent (mostly), or present (Themidaceae, Agapanthus). Stigmas wet type, or dry type; papillate. Placentation axile. Ovules 1–50 per locule (to many); campylotropous (usually), or anatropous (e.g. most Themidaceae); tenuinucellate (mostly), or crassinucellate (e.g. Agapanthus). Embryo-sac development Polygonum-type, or Allium-type. Antipodal cells formed; 3; not proliferating; ephemeral. Hypostase present. Endosperm formation nuclear, or helobial.
Fruit non-fleshy; dehiscent; a capsule. Seeds endospermic. Endosperm oily. Seeds winged (e.g., Agapanthus), or wingless. Seeds without starch. Cotyledons 1. Embryo achlorophyllous (2/5); straight to curved. Testa encrusted with phytomelan; black.
Seedling. Hypocotyl internode absent. Seedling collar not conspicuous. Cotyledon hyperphyll elongated (mostly), or compact; assimilatory (mostly), or non-assimilatory (e.g. in some Allium species); when elongated, more or less circular in t.s. Coleoptile absent. Seedling cataphylls present, or absent. First leaf centric, or dorsiventral. Primary root ephemeral.
Physiology, biochemistry. Cyanogenic (?), or not cyanogenic. Alkaloids absent. Proanthocyanidins absent (12 species). Flavonols present (mostly), or absent (e.g. Agapanthus); kaempferol, or kaempferol and quercetin. Ellagic acid absent. Saponins/sapogenins present. Inulin recorded (Allium, Gibbs 1974). C3. C3 physiology recorded directly in Allium. Anatomy non-C4 type (Allium).
Geography, cytology. Holarctic, Paleotropical, and Neotropical. Temperate, sub-tropical, and tropical. Cosmopolitan, but few in Australasia.
Taxonomy. Subclass Monocotyledonae. Dahlgren et al. Superorder Liliiflorae; Asparagales. APG 3 core angiosperms; Superorder Lilianae; non-commelinid Monocot; Order Asparagales (as a synonym of Amaryllidaceae).
Species 600. Genera 30 (according to Dahlgren et al. 1985, who do not list them all); Agapanthus, Allium, Ancrumia, Androstephium, Behria, Bessera, Bloomeria, Brodiaea, Dandya, Dichellostemma, Diphalangium, Erinna, Garaventia, Gethyum, Gilliesia, Ipheion, Leucocoryne, Miersia, Milla, Milula, Nectaroscordum, Nothoscordum, Milla, Muilla, Pabellonia, Petronymphe, Schickendantziella, Solaria, Speea, Trichlora, Tristagma, Triteleia, Triteleiopsis, Tulbaghia, Zoellnerallium.
General remarks. Fay and Chase (1996) resurrected Themidaceae (subsequently rejected?), and transferred Agapanthus to Amaryllidaceae, on the basis of rbcL DNA sequencing. These proposals have not yet been implemented here.
Economic uses, etc. Allium spp. supply onions and garlic.
Illustrations. • Technical details. • Technical details: Allium. • Allium ampeloprasum var. babingtonii: Eng. Bot. 1531 (1869). • Allium caeruleum : Bot. Reg. xxvi, 51 (1840). • Allium scorodoprasum: Eng. Bot. 1532 (1869). • Allium sphaerocephalon: as A. sphaerocephalum, Eng. Bot. 1533 (1869). • Allium ursinum (B. Ent.). • Allium vineale: Eng. Bot. 1534 (1869). • Bessera elegans: Bot. Reg. 1839, 34. • Ipheion uniflora: as Triteleia uniflora, Bot. Reg. 1921, 1837. • Nectaroscordum siculum: Bot. Reg. 1913 (1836). • Triteleia (Brodiaea) laxa: Bot. Reg. 1685, 1835.
His eyes were green as
O Sisters three
Come, come to me!
(Midsummer Nights Dream, v., 2)
And if the boy have not a womans gift
To rain a shower of commanded tears,
An onion will do well for such a shift
(Taming of the Shrew, introd.)
Mine eyes smell onions,
I shall weep anon
(Alls Well, v., 3)
This description is offered for casual browsing only. We strongly advise against extracting comparative information from it. This is much more easily achieved using the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG).
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 19th December 2012. http://delta-intkey.com’.