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双齿围沙蚕的雌性生殖腺比较特殊,始终没有上皮组织或结缔组织的膜包被,即不呈现一般生殖腺的具体形状。其生殖腺几乎分布于每一体节的体腔内成簇的生殖细胞团,卵原细胞团经增殖后发育到卵母细胞就散开,继续发育直至成熟。根据卵细胞形态特征,我们将卵细胞在体腔内的发育划分为卵原细胞期(第Ⅰ时相),无卵黄期(第Ⅱ时相)、卵黄形成期(第Ⅲ时期)和胶膜形成期(第Ⅳ时相)等四期。相应地根据各时相卵子的数量组成不同,把性腺发育分为增殖期、小生长期、大生长期和生殖期四个阶段。双齿围沙蚕周年都存在生殖细胞,并且周年中各时相卵细胞数量组成有明显变化。由此得出结果:双齿围沙蚕的繁殖期应在4—9月份,盛期应为5—6月份。
Bisexual Nereis of the female gonads rather special, there is always no epithelial tissue or connective tissue coating, that does not show the general shape of the gonads. Its gonads are distributed in clusters of germ cell clusters in the body cavities of almost every body segment. The oogonium cells proliferate and proliferate to the oocytes to disperse and continue to develop until maturity. According to the morphological characteristics of egg cells, we divided the development of egg cells in the body cavity into the stages of oogonium (stage Ⅰ), the stage of egg yolk (stage Ⅱ), the stage of yolk formation (stage Ⅲ) and the stage of film formation The fourth phase) and other four. Correspondingly, according to the composition of the number of eggs in each phase is different, the gonadal development is divided into proliferative phase, small growth phase, large growth phase and reproductive phase. Bisexual Nereis annual germ cells exist, and the number of each phase of the annual egg phase composition has changed significantly. The results obtained: Bisexual Nereis breeding season should be from April to September, the peak should be 5-6 months.