Cymbidium

Cymbidium , commonly known as boat orchids, is a genus of evergreen flowering plants in the orchid family Orchidaceae. Orchids in this genus are epiphytic, lithophytic, terrestrial or rarely leafless saprophytic herbs usually with pseudobulbs. There are usually between three and twelve leaves arranged in two ranks on each pseudobulb or shoot and lasting for several years. From one to a large number of flowers are arranged on an unbranched flowering stem arising from the base of the pseudobulb. The sepals and petals are all free from and similar to each other. The labellum is significantly different from the other petals and the sepals and has three lobes. There are about fifty-five species and sixteen further natural hybrids occurring in the wild from tropical and subtropical Asia to Australia. Cymbidiums are well known in horticulture and many cultivars have been developed. The genome of Cymbidium mannii has been sequenced to study epiphytism and crassulacean acid metabolism.

==Description== Plants in the genus Cymbidium are epiphytic, lithophytic or terrestrial plants, or rarely leafless saprophytes. All are sympodial evergreen herbs. Some species have thin stems but in most species the stems are modified as pseudobulbs. When present, there are from three to twelve leaves arrange in two ranks and last for several years. The leaf bases remain after the leaf has withered, forming a sheath around the pseudobulb. The flowers are arranged on an unbranched flowering stem which arises from the base of the pseudobulb or rarely from a leaf axil. The sepals and petals are usually thin and fleshy, free from, and more or less similar to each other. The labellum (as in other orchids, a highly modified third petal) is significantly different from the other petals and sepals. It is sometimes hinged to the column, or otherwise fused to it. The labellum has three lobes, the side lobes erect, sometimes surrounding the column and the middle lobe often curving downwards. After pollination a glabrous capsule containing many light coloured seeds is produced. thumb|Labelled image of Cymbidium aloifolium