Umbelliferae

Umbelliferae

[‚əm·bə′lif·ə‚rē]

(botany)

A large family of aromatic dicotyledonous herbs in the order Umbellales; flowers have an ovary of two carpels, ripening to form a dry fruit that splits into two halves, each containing a single seed.

Umbelliferae

 

(Apiaceae), a family of dicotyledonous plants related to the ginseng family. They are herbaceous plants—sometimes shrubs and small trees in the tropics and subtropics—with alternate, usually dissected coleophyllous leaves and often hollow stems. The inflorescences are compound but sometimes simple umbels or heads. The small flowers are usually bisexual and regular. The calyx, consisting of five small denticles at the apex of the gynaecium, is often inconspicuous but may sometimes be well developed. There are five petals and stamens, with the petal apexes usu-ally curved inward. The pistil has a half-inferior bilocular gynaecium and large developed honeycups. The fruit is a cremocarp, usually breaking up into dry monospermous lobes (mericarps) which hang from either an entire or, more often, bipartite column (carpophore). The seed has an endosperm and a small embryo and is usually fused with the pericarp. All the organs have well-developed conceptacles for essential oils and resins.

The family comprises over 280 genera (about 3,000 species), distributed over almost the entire globe, especially in the nontropical regions of the northern hemisphere. There are 140 genera (about 750 species) in the USSR. The family includes many useful plants: food plants (carrots, parsley, celery, dill, parsnip, caraway, coriander), essential-oil plants (coriander, anise, fennel, caraway, ajowan), and medicinal and industrial plants. Some members of the family are very toxic, including hemlock, cowbane, and fool’s-parsley. A number of species grow as weeds among crops.

REFERENCE

Flora SSSR, vols. 16–17. Moscow-Leningrad, 1950–51.

V. N. TIKHOMIROV