Abstract

The metamorphosis of spermatozoid and the formation of operculum in microgametophyte of Selaginella tamariscina (Beauv.) Spring are studied under EM. The distinct during the metamorphosis are: (1) the elongation of the apical mitochondrion, (2) the separation of basal bodies and emergence of flagella, (3) thy elongation of nucleus and (4) discard of excess cytoplasm. The formation and opening process of operculum described are the significant finding of microgametophytes in heterosporous lycopods. Operculum is derived from several jacket cells. After the operculum takes off, the spermatozoids spring out in a clump. Occasionally the jacket cells give rise to the spermatids, too. A mature spermatozoid has a twisted long nucleus, an apical mitochondrion with or without a posterior mitochondrion, a posterior plastid containing several large starch grains and large flagella. The anterior flagellum exserts from the apex of the apical mitochondrion, while the posterior one exserts fron the juncture of the apical mitochondrion and the nucleus.

中文摘要

本文於電子顯微鏡下觀察萬年松Saleginella tamariscina (Beauv.) Spring精細胞成熟的過程：變態及「囊蓋」(operculum)的形成。變態包括下列變化：(1)前端粒線體的延長、(2)基體(basal bodies)的分離及鞭毛的伸展、(3)細胞核的延長(4)剩餘細胞質的排除。 在產生異型配子的石松族中，雄配子體形成過程中「囊蓋」的形成與開啟為本研究之創見。「囊蓋」由一些保護層細胞組成，當「囊蓋」掀開後，精細胞成團湧出。偶亦見保護層細胞發育成精細胞。 成熟的精細胞具有細長而扭曲的細胞核、一個前端粒腺體、有或無一個末端的粒腺體、一個內含數顆大澱粉粒的末端色素體、及兩根鞭毛。前鞭毛自前端粒腺體的先端伸出細胞外，後邊毛自前端粒腺體的與細胞核之間伸出。