The families of flowering plants.
Habit and leaf form. Highly aromatic, glabrous trees (mostly), or shrubs (rarely); bearing essential oils. Leaves evergreen; alternate; leathery; petiolate; non-sheathing; gland-dotted; aromatic; simple. Lamina entire; pinnately veined. Leaves exstipulate. Lamina margins entire.
Leaf anatomy. Stomata present; paracytic (usually), or anomocytic.
The mesophyll with spherical etherial oil cells; containing calcium oxalate crystals. The mesophyll crystals druses. Minor leaf veins without phloem transfer cells (Canella).
Stem anatomy. Cork cambium present; initially superficial. Nodes tri-lacunar, or bilacunar (with three traces, according to Lammers et al. 1986). Internal phloem absent. Secondary thickening developing from a conventional cambial ring. ‘Included’ phloem absent. Xylem with tracheids. Vessel end-walls oblique; scalariform and reticulately perforated. Vessels without vestured pits. Wood parenchyma apotracheal, or paratracheal, or apotracheal and paratracheal. Sieve-tube plastids P-type; type I (c).
Reproductive type, pollination. Plants hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’; when solitary, axillary; when aggregated, in cymes, or in racemes. The ultimate inflorescence unit cymose, or racemose. Inflorescences terminal, or axillary; cymes or racemes. Flowers regular; cyclic, or partially acyclic. When partially acyclic, the perianth acyclic (the petals). Floral receptacle not markedly hollowed. Free hypanthium absent. Hypogynous disk absent.
Perianthwith distinct calyx and corolla, or sequentially intergrading from sepals to petals (depending on whether the three thick, leathery, persistent outer members are interpreted as sepals or bracts); (7–)8–15; free, or joined; 2–3(–5) whorled; anisomerous. Calyx 3 (if the outer members are not interpreted as bracts), or 4–5 (interpreting the outer whorl of ‘petals’ as sepals); 1 whorled; polysepalous; regular; imbricate. Corolla (4–)5–12; when cyclic, 1–2(–4) whorled; polypetalous, or partially gamopetalous, or gamopetalous. Corolla lobes about the same length as the tube, or markedly longer than the tube (corolla connate at the base in Canella, to the middle in Cinnamosma). Corolla imbricate. Petals slender.
Androecium 6–12 (mostly), or 35–40 (Cinnamosma). Androecial members free of the perianth; coherent; 1 adelphous (completely connate into a tube, with the anthers attached on its outside). Androecium exclusively of fertile stamens. Stamens 6–12, or 35–40 (Cinnamosma); with sessile anthers (these adnate to the staminal tube). Anthers adnate; non-versatile; dehiscing by longitudinal valves; extrorse; tetrasporangiate (each with two juxtaposed bisporangiate thecae). Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral. Anther wall initially with more than one middle layer. Tapetum glandular. Pollen shed as single grains. Pollen grains aperturate; 1 aperturate; sulcate (or the aperture V-shaped or trichotomous); 2-celled.
Gynoecium 2–5(–6) carpelled. The pistil 1 celled. Gynoecium syncarpous; synstylovarious to eu-syncarpous; superior. Ovary 1 locular. Gynoecium stylate. Styles 1; apical (short and thick). Stigmas 1; 2–6 lobed. Placentation parietal. Ovules in the single cavity 6–100 (two to ‘many’ on each placenta); horizontal to ascending; in a single or double row on each placenta; hemianatropous; bitegmic; crassinucellate. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating. Synergids pear-shaped.
Fruit fleshy; indehiscent; a berry; 2–100 seeded (to ‘many’). Seeds copiously endospermic. Endosperm ruminate (in Cinnamosma only), or not ruminate; oily. Embryo well differentiated (small). Cotyledons 2. Embryo slightly curved, or straight. Micropyle zigzag.
Physiology, biochemistry. Cyanogenic. Alkaloids present (one of the species), or absent. Proanthocyanidins absent. Flavonols absent. Ellagic acid absent (Canella). Saponins/sapogenins absent. Aluminium accumulation not found.
Geography, cytology. Paleotropical and Neotropical. Tropical. West Indies and Florida, tropical South America and East Africa, Madagascar. 2n = 22, 26, 28.
Taxonomy.Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Magnoliiflorae; Annonales. Cronquist’s Subclass Magnoliidae; Magnoliales. APG 3 core angiosperms; Superorder Magnolianae; Order Canellales.
Species 16. Genera 6; Canella, Capiscodendron, Cinnamodendron, Cinnamosma,Pleiodendron, Warburgia.