FLORA OF VIETNAM. Fam. Convallariaceae. Ophiopogon sp. N. Vietnam, prov. Ha Giang, distr. Yen Minh, municipality Lao Va Chai,. vicinities of Ngan Chai village, 6 km to W of Yen Minh town (N 23°07'. E 105°08'). Primary evergreen wet mossy mixed forest (with domination. of Tsuga chinensis and Pinus kwangtungensis) along tops of karst. remnant limestone ridge at 1500-1600 m elev. Terrestrial herb on shady. steep slopes. Flowers blue-violet. Very common. Usual codominante of. herb forest stratum. No CBL 1889 01 May 1999. International Botanical Expedition of the U.S.A. National Geographic. Society (grant No 6300-98). . Collectors: P.K.Loc, P.H.Hoang, Averyanov L.