An Electron Microscopy of Spermiogenesis in the Dragonfly, Crocothemis servilia Drury

고추잠자리의 精子完成의 電子顯微鏡的 硏究

Ultrastructures of spermiogeneis in other invertebrates were investigated by several workes (Anderson, et al., 1967; Bloch, et al., 1964; Christen, 1961; Gatenby, et al., 1959; Paik, et al., 1968; Silveira, 1964; Yasuzumi, 1957) but spermiogenesis of dragonfly has not been reported previously. Testes and vass deferentia of the Korean dragonfly, Crocothemis servilia, were used for electron microscopic study of spermiogenesis. Materials were prefixed for 1-2 hours at $3^{\circ}C$ in 1.25% glutaraldehyde buffered to pH 7.2 with 0.2M sodium cacodylate buffer. Fixed tissue was washed twice in 0.2M cacodylate buffer and was subsequently postfixed for 2 hours at $3^{\circ}C$ in 1% osmium tetroxide buffered to pH 7.2 with 0.4M sodium cacodylate buffer solution. Specimens were dehydrated in graded ethyl alcohol, and finally embedded in epoxy Epon resin. Thin sections prepared from all the blocks were doubly stained; first in uranyl acetate and then in lead citrate. All thin sectios were examined with a Hitachi HS-7S electron microscope. The results of this study were summarized as follows. 1. Along the condensation of chromatin in nucleus, the shpae of nucleus was changed from spherical shpae to ellipse and cone cell type. 2. During the elongation of nucleus and the migration of cytoplasm, the nucleus removed to the one side of spermatid and began to invaginate from the posterior portion of nucleus. 3. There are ring centrioles in invaginated portion and axial filaments derived from centriole extend to the tail through the tailward half of spermatid. 4. In the cross sections the axial filament consisted of a central sheath, a central fibril, and 9 peripheral doublets.

고추잠자리(Crocothemis servilia Drury)의 精子完成過程을 究明하기 爲하여, 本 硏究에 着手한 바, 다른 無脊椎動物의 精子完成過程에서 이미 밝혀진 構造들과 比較해 가면서 特殊한 分化相을 觀察한 結果, 첫째 核의 染色質이 漸次 濃縮되기 始作함에 따라서 核의 모양도 球形에서 楕圓形으로, 楕圓形에서 圓錐形으로 變하였으며 둘째로 核이 細胞의 一極端으로 移動하고 核의 尾部가 陷入되며 셋째 中心粒이 核 陷入 部位에 位置하여 여기에서부터 軸　가 形成된다. 넷째는 골지體에서 起因된 尖體顆粒은 核의 先端으로 移動되어 결국 尖體를 形成하게 된다.