Studies on the chemical constituents in herb of Lygodium japonicum Structure and Development of Sporoderm of Lygodium japonicum (Thunb.) Sw.(Lygodiaceae) An Ultrastructural Study of the Development of Blepharoplast and the Origin of Multilayered Structure in the Sperm of Lygodium japonicum Studies on the Development of Embryo in Lygodium japonicum (Thunb.) Sw. Development of Gametophyte and Oogenesis of the Fern Lygodium japonicum A New Observation on Several Morphological Characteristics of Gametophyte in Lygodium japonicum