@article{oai:ynu.repo.nii.ac.jp:00001642, author = {Sato, Yoshihiko}, journal = {横浜国立大学理科紀要. 第二類, 生物学・地学}, month = {Nov}, note = {application/pdf, The development of embryo sacs in Cephalanthera erecta var. erecta, C. erecta var. subaphylla and C. falcata was investigated. In these three orchids the ovules are anatropous, tenuinucellate and bitegmic. In some ovules of C. falcata and C. longibracteata, it was observed that the anatropous and bitegmic condition was brought much delayed. The largest megaspore of a tetrad, which is farthest from the micropyle, becomes functional and its nucleus divides three times in succession, so that a mature embryo sac is always composed of eight nuclei. The developmental mode of embryo sacs in these three orchids is usually of the monosporic eight nucleate type. The embryological features of Cephalanthera investigated were compared with those of Epipactis, which is closely related genus of Cephalanthera.}, pages = {1--9}, title = {Development of the Embryo Sac in Some Japanese Members of Cephalanthera (Orchidaceae)}, volume = {26}, year = {1979} }