Excluding Aucubaceae, Curtisiaceae, Davidiaceae, Griseliniaceae, Helwingiaceae, Mastixiaceae, Melanophyllaceae, Nyssaceae, Toricelliaceae
Habit and leaf form. Trees and shrubs, or herbs (rarely). Plants non-succulent. The herbs perennial; rhizomatous. Leptocaul. Mesophytic. Leaves evergreen, or deciduous; opposite (nearly always), or alternate (rarely spiral); `herbaceous', or leathery; usually petiolate; almost connate, or not connate; non-sheathing; gland-dotted, or not gland-dotted; simple; epulvinate. Lamina entire (usually), or dissected (rarely); pinnately veined; cross-venulate. Leaves exstipulate. Vegetative buds scaly, or not scaly. Leaves without a persistent basal meristem. Domatia recorded (from 4 genera); represented by pockets (mostly), or hair tufts.
General anatomy. Plants with `crystal sand', or without `crystal sand'.
Leaf anatomy. Stomata present; usually anomocytic.
Adaxial hypodermis absent. Lamina dorsiventral. Minor leaf veins without phloem transfer cells (Cornus).
Stem anatomy. Cork cambium present; initially superficial. Nodes tri-lacunar. Secondary thickening developing from a conventional cambial ring. Xylem with tracheids; with vessels. Vessel end-walls scalariform. Vessels without vestured pits. Wood parenchyma apotracheal.
Reproductive type, pollination. Hermaphrodite (usually), or dioecious.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in `inflorescences'; in cymes, in heads, in corymbs, and in umbels. The terminal inflorescence unit cymose. Inflorescences terminal, or axillary; usually in cymes, cymose corymbs, panicles or umbels, in racemes of panicles, or even in heads; with involucral bracts (sometimes), or without involucral bracts; pseudanthial (sometimes), or not pseudanthial. Flowers bracteate; small to medium-sized; regular; 4-5 merous; cyclic; tricyclic, or tetracyclic. Free hypanthium absent.
Perianth with distinct calyx and corolla, or sepaline; 4-5, or 8-10; 1 whorled, or 2 whorled; isomerous (usually), or anisomerous. Calyx when resolvable 4-5(-7); 1 whorled; gamosepalous (sepals free as no more than small teeth); entire, or lobulate, or lobed, or toothed; regular; valvate, or open in bud. Corolla when present, 4-5; 1 whorled; when present, polypetalous; valvate; regular; not fleshy.
Androecium 4-5. Androecial members free of the perianth; all equal; free of one another; 1 - whorled. Androecium exclusively of fertile stamens. Stamens 4, or 5; isomerous with the perianth; oppositisepalous. Anthers dehiscing via longitudinal slits; introrse; tetrasporangiate. Microsporogenesis simultaneous. Pollen shed in aggregates (occasionally), or shed as single grains; when aggregated, in tetrads. Pollen grains aperturate; 3 - aperturate; colporate; 2-celled.
Gynoecium 2(-4). Carpels reduced in number relative to the perianth. Gynoecium syncarpous (but occasionally pseudomonomerous); synovarious to eu-syncarpous; inferior. Ovary 1 locular (occasionally, pseudomonomerous), or 2-3(-4) locular. Epigynous disk present. Gynoecium stylate. Styles 1, or 2-4; free, or partially joined; apical. Stigmas dry type; non-papillate; Group II type. Placentation when unilocular parietal; usually axile, or apical. Ovules in the single cavity when unilocular, 1; 1 per locule; pendulous; apotropous; with dorsal raphe (?always); non-arillate; anatropous; unitegmic; crassinucellate (usually). Endothelium differentiated. Embryo-sac development Polygonum-type, or Fritillaria-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; ephemeral. Synergids pear-shaped. Hypostase present, or absent. Endosperm formation cellular.
Fruit fleshy; indehiscent; a drupe (usually), or a berry (less often). Seeds endospermic. Endosperm oily. Cotyledons 2. Embryo chlorophyllous (3/4).
Seedling. Germination phanerocotylar.
Physiology, biochemistry. Not cyanogenic. Alkaloids present (commonly), or absent. Iridoids recorded (often aucubin); carbocyclic and seco-compounds. Proanthocyanidins present, or absent (mostly); when present, cyanidin. Flavonols present; quercetin, or kaempferol and quercetin. Ellagic acid present (Cornus, Macrocarpium). Arbutin absent. Ursolic acid present. Saponins/sapogenins present (rarely), or absent. Aluminium accumulation demonstrated. Inulin recorded. C3. C3 recorded in Cornus.
Geography, cytology. Temperate (mainly), or sub-tropical to tropical (in mountains). North and South temperate, and tropical mountains, few in Australia. X = 8-13, 19.
Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren's Superorder Corniflorae; Cornales. Cronquist's Subclass Rosidae; Cornales. Takhtajan's Subclass Rosidae; Aralianae; Cornales. Species about 60 (?). Genera 1-6 (depending on recognition of segregate genera); Cornus (including Afrocrania, Benthamidia, Chamaepericlymenum, Cynoxylon, Swida, Yinquania etc.).
Economic uses, etc. Good edible berries from several species, especially Cornus mas.
Illustrations. corna476.gif corna782.gif
