中文摘要：

采用连续组织切片对半滑舌鳎胚胎及仔鱼进行了观察研究,首次描述了半滑舌鳎胚胎发育过程中原始生殖细胞（primordial germ cells,PGCs）出现的部位及迁移特征,以及卵黄合胞体,鳔与性腺原基的发育分化.结果发现,PGCs出现于神经胚期的靠近卵黄囊的囊胚层.PGCs的特征为体积比周围细胞大,核大透亮,随后在肌肉期的脊索壁上出现.孵化前期的PGCs迁移到肠原基附近,肠系膜旁可见尚在移动的PGCs和10日龄的仔鱼中在肾管旁出现性腺原基,以后PGCs数量逐渐增多参与性腺的形成.本研究为半滑舌鳎的发育生物学以及养殖生产实践提供参考.

英文摘要：

Embryos and larvae of Cynoglossus semilaevis were observed and studied by using histological technique.The origin of the site and emerging features of primordial germ cells were described for the first time in C.semilaevis embryonic development,and the development and differentiation of yolk syncytical,swim bladder and primitive gonad were found at the same time.The results showed that PGCs appear in the yolk sac near the blastoderm during neurula period.PGCs were characterized by large volume than the surrounding cells and had large nuclie,Subsequently appeared in wall of the notochord during the muscle period.Pre-incubation of the PGCs migrated to the vicinity of intestinal primordium.Mesenteric side of the PGCs could be seen still moving,gonadal primordium appeared next to Nephridium tube in10-day-old larvae.After gradually increasing the number of PGCs,PGCs participated in the formation of gonadal.The study provided basic information on developmental biology and aquaculture production practices of C.semilaevis.