龙须草成熟胚囊结构和类型的观察

STUDIES ON THE STRUCTURE AND TYPE OF MATURE EMBRYO SAC IN Eulaliopsis binata

采用常规石蜡切片法，观察了龙须草成熟胚囊的结构和类型。结果表明：龙须草的成熟胚囊通常是由靠近珠孔端的１个４核胚囊分化而来；发育类型为体细胞无孢子生殖的大黍型；成熟胚囊由１个卵细胞、２个助细胞和含１个极核的中央细胞组成。

The formation and type of mature embryo sac in Eulaliopsis binata were studied by using the method of routine paraffin sectioning. The result showed: the four nucleate cmoryo sac at the micropylar end usually differentiated into a mature embryo sac with two synergids, one egg, one polar nucleus, and no antipodals. Moreover, there were occasional embryo sac with one synergid, one egg, and two polar nuclei. The normal type leight nuclei and seven cells has not been found. The type of development of the aposporous embryo sac resembles the panicum type. And many abnormal deuelopment phenomena of ovule were also discussed.