Cephalanthera Rich., Mém. Mus. Hist. Nat. 4: 51 (1818).
Synonyms:
Callithronum Ehrh., Beitr. Naturk. 4: 148 (1789).
Lonchophyllum Ehrh., Beitr. Naturk. 4: 148 (1789).
Dorycheile Rchb., Deut. Bot. Herb.-Buch: 56 (1841).
Xiphophyllum Ehrh., Beitr. Naturk. 4: 148 (1879).
Eburophyton A.Heller, Muhlenbergia 1: 48 (1904).
Tangtsinia S.C.Chen, Acta Phytotax. Sin. 10: 194 (1965).
Description:
Herbs terrestrial or saprophytic [not parallel, why not autotrophic or saprophytic, or terrestrial or epiphytic, usually with a short rhizome and tufted fleshy roots, but saprophytic plants with relatively long rhizomes and scattered fleshy roots. Stem erect, not branched, usually with several leaves above middle, covered below by nearly cymbiform or cylindrical sheaths.
Leaves alternate, plicate, base subsessile and clasping, reduced into membranous sheaths in saprophytic species. Raceme terminal, several or many flowered, rarely a solitary flower; bracts often small, sometimes lowest 1 or 2 +/- leaflike.
Flowers zygomorphic, suberect or spreading, +/- resupinate, often not opening widely. Sepals similar. Petals often slightly shorter than sepals, sometimes +/- connivent with sepals forming tube; labellum 3-lobed, with a gibbous sac or short spur at base; lateral lobes small, often +/- embracing column; midlobe spreading, adaxially with 3--5 lamellae. Column erect, subterete; anther terminal, incumbent, erect, 2-loculed; filament conspicuous; staminodes 2, white, spotted with silver; pollinia 2, each 2-parted, granular-farinaceous, lacking either caudicle or viscidium; stigma concave, on front side of column near apex; rostellum inconspicuous.
Fruit a capsule.
Distribution:
N. Africa, Temp. Eurasia to Indo-China, W. North America
Species:

Cephalanthera damasonium (Mill.) Druce  Europe to N. Iran, Bhutan to China (Yunnan).
Cephalanthera longifolia (L.) Fritsch Europe, Medit. to C. China.
Cephalanthera rubra (L.) Rich. Europe to C. Asia.

World Checklist of Monocotyledons. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/monocots/ accessed 04/07/2020
Bibliography and References:
Pearce N, Cribb PJ, Renz J. 2001 Notes relating to the flora of Bhutan: 34. Taxonomic notes, new taxa and additions to the Orchidaceae of Bhutan and Sikkim (India). Edinburgh J. Bot. 58. (1): 99-122 (2001)
Cribb PJ, Chen SC. 1997 The true identity of Cephalanthera yunnanensis Hand.-Mazz. (Orchidaceae). Lindleyana 12. (1): 16-18 (1997)