Flavanthridin and flavanthrinin, two new stilbenoids, were isolated from the orchid Eria flava which also afforded 2,7-dihydroxy-4-methoxy-9,10-dihydrophenanthrene (coelonin), its 1,1′-dimer (flavanthrin) and 3,7-dihydroxy-2,4-dimethoxyphenanthrene of previously known structures. The structures of flavanthridin and flavanthrinin were established as 3,7-dihydroxy-2,4-dimethoxy-9,10-dihydrophenanthrene and 2,7-dihydroxy-4-methoxyphenanthrene respectively. © 1990.