原叶体

蕨类植物的配子体.微小，大多生活时期较短，无根、茎、叶的分化，仅具假根.其上产生精子器和颈卵器，在有水的条件下完成受精过程.当受精卵分裂发育成胚、幼孢子体长出后，原叶体逐渐枯萎.不同的蕨类其原叶体的形态、大小和营养方式也有差异.如松叶蕨的原叶体呈不规则圆柱状，埋入土中，无叶绿体，体内具维管组织，有真菌与其共生；石松类的原叶体呈长圆形、胡萝卜状或圆盘状，在土中生长的部分均为无色或黄色到褐色，而暴露在地表的部分为绿色，也有真菌共生；木贼类的原叶体为垫状，具直立的带状分枝，绿色自养；真蕨类的原叶体多为心形，绿色自养，也有的呈丝状或带状.Fern gametophyte. Small, tend to live a shorter period, no roots, stems, leaf differentiation, only a rhizoid. Device on which to produce sperm and the archegonium, where fertilization of water under the conditions to complete the process. When fertilization eggs develop into the embryo splitting, young sporophyte grow after the prothallus gradually withering away. different species of fern leaves its original body shape, size and nutritional ways are different. If the original pine needles fern leaf lanes are irregular cylindrical , in the earth, no chloroplast, in vivo with vascular tissue, with their symbiotic fungi; Song-class of the original leaf lanes are long round, carrot-shaped or disc-shaped, part of the growth in the soil are colorless or yellow to brown , while the exposed parts of the surface is green, there are symbiotic fungi; Equisetum class prothallus of cushion-like, with upright branches of the ribbon, green self-supporting; true prothallus of ferns are mostly heart-shaped, green self-supporting, while others showed filamentous or ribbon.