The families of flowering plants
Habit and leaf form. Trees and shrubs; bearing essential oils, or without essential oils. Mesophytic. Leaves evergreen, or deciduous; medium-sized, or large; alternate; spiral; herbaceous, or leathery; petiolate; sheathing (via the stipules); gland-dotted, or not gland-dotted; aromatic, or without marked odour; simple. Lamina dissected (Liriodendron), or entire; (of Liriodendron) pinnatifid, or palmatifid (with truncate or emarginate apices); pinnately veined, or palmately veined; cross-venulate. Leaves stipulate (the stipules large, sheathing, enclosing the terminal buds). Stipules ochreate (often), or not ochreate; caducous. Leaf development not graminaceous.
Leaf anatomy. Stomata paracytic, or anomocytic and paracytic. Adaxial hypodermis present, or absent. The mesophyll with spherical etherial oil cells, or without etherial oil cells (sometimes?); containing mucilage cells, or not containing mucilage cells. Minor leaf veins without phloem transfer cells (Magnolia).
Axial (stem, wood) anatomy. Pith with diaphragms, or without diaphragms. Cork cambium present; initially superficial. Nodes penta-lacunar, or multilacunar (with five or more traces). Primary vascular tissues comprising a ring of bundles (at first), or in a cylinder, without separate bundles; collateral. Internal phloem absent. Cortical bundles absent. Medullary bundles absent. Secondary thickening developing from a conventional cambial ring. Primary medullary rays wide.
The wood diffuse porous. The vessels small, or medium; solitary, radially paired, in radial multiples, and clustered. The vessel end-walls scalariform (mostly, usually), or scalariform and simple. The vessels without vestured pits; commonly with spiral thickening. The axial xylem with tracheids, or without tracheids; with fibre tracheids, or without fibre tracheids; including septate fibres (rarely, obscurely), or without septate fibres. The parenchyma apotracheal (terminal). The secondary phloem stratified into hard (fibrous) and soft (parenchymatous) zones, or not stratified. Included phloem absent. The wood not storied. Tyloses present (often), or absent.
Reproductive type, pollination. Plants hermaphrodite (usually), or monoecious (Kmeria). Pollination entomophilous; via beetles.
Inflorescence, floral, fruit and seed morphology. Flowers usually solitary; terminal, or axillary; bracteate (the bracts spathaceous); large; regular; partially acyclic, or acyclic. The perianth acyclic, the androecium acyclic, and the gynoecium acyclic, or the androecium acyclic and the gynoecium acyclic. Floral receptacle not markedly hollowed (on the contrary, usually markedly elongated). Free hypanthium absent. Hypogynous disk absent.
Perianth with distinct calyx and corolla (rarely), or sequentially intergrading from sepals to petals, or petaline (usually); 6–18; free; when not spiralled, 3–4 whorled; white, or cream, or pink; deciduous.
Androecium 50–200 (many). Androecial members maturing centripetally; free of the perianth; free of one another; spiralled. Androecium exclusively of fertile stamens. Stamens 50–200 (many); more or less filantherous, or laminar (the four paired microsporangia embedded, the stamens often more or less strap-shaped). Anthers adnate; non-versatile; dehiscing via longitudinal slits, or dehiscing by longitudinal valves; extrorse (Liriodendron), or latrorse to introrse (usually, the thecae nearly lateral); bilocular; tetrasporangiate; appendaged (often, by prolongation of the connective), or unappendaged. Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads isobilateral, or decussate. Anther wall initially with more than one middle layer (up to four). Tapetum glandular. Pollen shed as single grains. Pollen grains aperturate; 1 aperturate; sulcate; 2-celled.
Gynoecium (2–)20–200 carpelled; apocarpous; eu-apocarpous; superior. Carpel fully closed, or incompletely closed; stylate; apically stigmatic; 2(–20) ovuled. Placentation marginal. Ovules funicled; pendulous; biseriate (on the ventral suture); anatropous; bitegmic; crassinucellate. Outer integument contributing to the micropyle. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; ephemeral. Synergids pear-shaped. Endosperm formation cellular. Embryogeny onagrad.
Fruit fleshy, or non-fleshy; an aggregate. The fruiting carpels coalescing into a secondary syncarp (woody or fleshy), or not coalescing. The fruiting carpel dehiscent, or indehiscent; a follicle, or samaroid (Liriodendron), or baccate. Seeds endospermic. Endosperm oily. Seeds usually large. Embryo well differentiated (usually very small, larger in Liriodendron). Embryo achlorophyllous (2/2).
Seedling. Germination phanerocotylar.
Physiology, phytochemistry. C3. C3 physiology recorded directly in Magnolia. Sugars transported as sucrose (Liriodendron), or as sugar alcohols + oligosaccharides + sucrose (Magnolia kobus). Cyanogenic. Cynogenic constituents tyrosine-derived. Alkaloids present (often), or absent. Arbutin absent. Iridoids not detected. Proanthocyanidins present (rarely), or absent; when present, cyanidin. Flavonols present; kaempferol and quercetin. Ellagic acid absent (2 genera, 8 species). Aluminium accumulation demonstrated. Sieve-tube plastids S-type, or P-type and S-type; when P-type, type I (b).
Geography, cytology. Temperate to tropical. Eastern Asia and America. X = 19. Supposed basic chromosome number of family: 19.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgrens Superorder Magnoliiflorae; Magnoliales. Cronquists Subclass Magnoliidae; Magnoliales. APG 3 core angiosperms; Superorder Magnolianae; Order Magnoliales.
Species about 230. Genera 5–12 (depending on differing interpretations of Magnolia); Kmeria, Liriodendron, Magnolia sensu lato (including Alcimandra, Aromadendron, Elmerrillia, Paramichelia, Talaumia, Tsoongiodendron), Manglietia, Michelia, Pachylarnax.
Illustrations. • Technical details: Magnolia. • Liriodendron tulipifera: Bot. Mag. 275, 1794. • Liriodendron chinense: Hook. Ic. Pl. 28 (1905). • Magnolia campbelii, detailing flowers and fruits: Hooker’s Illustrations of Himalayan plants (1855). • Magnolia cf. liliifera: as Talauma, Bot. Reg. 1709, 1835. • Magnolia hodgsonii (as Talauma hodgsoni): Hooker’s Illustrations of Himalayan plants (1855). • Magnolia purpurea: Bot. Mag. 390, 1797. • Magnolia purpurea: Bot. Mag. 390, text. • Magnolia cathcarti (as Michelia): Hooker’s Illustrations of Himalayan plants (1855). • Magnolia nilagirica (as Michelia pulneyensis): R. Wight (1840).
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or 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). See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 20th June 2017. delta-intkey.com/angio’.