海金沙胚胎发育的研究

利用石蜡切片法研究了海金沙胚胎发育过程。合子的第一次分裂面垂直于颈卵器的长轴，产生两个相等的子细胞，靠近颈卵器颈部的营养器官原始细胞和远离颈部的基足原始细胞。前者发育成子代孢子体的营养器官，后者发育成基足。胚胎在32细胞阶段后，第一叶顶端细胞与第一根顶端细胞几乎同时发生。第一叶突出帽状体之后，由第一叶基部保留下来的茎干顶端细胞产生第二叶。据营养器官的形态结构判断，在海金沙胚胎发育中最早出现的营养器官是叶和根。

Studies on the Development of Embryo in Lygodium japonicum(Thunb.) Sw.

This paper gives some details about the development of embryo in Lygodium japonicum(Thunb.)Sw. using the method of serial sections. In this species, the first division of zygote produces two equal hemispheric cells by the first partition wall at the right angles to the axis of the archegonium. The daughter cell near the neck of the archegonium gives rise to the vegetable organs, the other cell away from the neck develops to the feet. The apical cell of the first leaf and of the first root originate almost at the same time after the embryo reaches to the 32-celled phase. The second leaf takes place at the basal part of the first leaf and originates from the shoot apex cells when the first leaf pierces the calyptra. On the basis of the structure of vegetable organs, the first leaf and root are the earliest organs in the development of embryo.