【摘要】 本文研究了掌叶铁线蕨配子体的发育。孢子四面体形,三裂缝。扫描电镜下见其外壁具大小不等的片状扁平突起。孢子萌发为向心型,丝状体一般为2—5胞细,单列,有时细胞多列。原叶体发育铁线蕨型。原叶体为裸露的心脏形,长倒卵形成宽倒卵形。雌雄异株。精子器长圆状圆球形,盖细胞不分裂。颈卵器较大,颈部细胞高。掌叶铁线蕨的孢子形态和萌发、生殖器较大等特点,均表现为原始形式。但铁线蕨属中的精子器盖细胞,有的种分裂,有的种不分裂,而掌叶铁线蕨的则为不分裂,可能是该属种演化水平较高的种。更多还原

【Abstract】 The deyelopment of gametophytes of Adiantum pedatum L. wassas studied. The spore is tetrahedral, 28.93×42.57u,trilete andobtuse triangular in polar view, semiorbicular in equatorialview,with variously large or small lamellar flat ornamentationsobserved by scanning electron microscope. The pattern of sporegermination is of centripetal type (Momose (1942). Generallythe germ filaments develop 2--5 cells long, uniseriate, some-timesto 7 cells long or multiseriate. The prothallial developmentis of the Adiantum type (Nayar 1971). The prothalli mature in 7--11 weeks after inoculum. Theyare naked and cordate, long obovate or broad obovata, lengthlonger than width, about 5.5×4mm. Thc plants are strictlydioecious. Thc antheridia are long rounded globular, 50.68-55.1u in diameter. They always occur on the margin or sur-face of young prothalli. Its operculum is single. Each antheri-dium contaius about 30--31 spermatozoids, 30--49 flagellated.The archegonia develop on the midrib of matured prothalli.Its neck of is 5--6 celled high and reaches a length of 101.36-131.57u. Vegetative propagation is common in this species. The present work and another paper (Kachroo & Nayar 1953)show that the spore of genus Adiantum is tetrahedral and ger-mination pattern is centripetral,and its sex organs of that arerather large. It implies that these are common primitive char-ateristics of the genus. But the opereulum of antheridium ofAdiantum pedatum is single, while the opcrculum of other speciesit divided (Kachroo & Nayar 1953). If single operculm isanudvanced charater, Adiantum pedatum might be higher evolutionarylevel in this genus.更多还原