星突江鲽胚胎发育的研究

对人工干法授精、微量充气孵化条件下星突江鲽的胚胎发育进行了研究。星突江鲽受精卵为分离的球形浮性卵，无油球、卵膜薄、光滑且透明，具弹性。吸水前卵径为0．66～0．70mm，吸水后为0．91～1．06mm。根据胚胎发育的外部形态及典型特征将星突江鲽胚胎发育过程划分为卵裂期、囊胚期、原肠期、神经胚期、胚孔关闭、眼泡和肌节形成、尾芽形成、晶体出现、听囊出现、出膜前期和出膜期11个连续的典型时期。在11±0．5℃水温下，受精卵经过101h仔鱼脱膜孵出。初孵仔鱼全长2．3～2．5mm，卵黄囊长径1．075～1．25mm，短径0．60～0．675mm。

Study on the embryonic development of starry flounder Platichthys stellatus

This paper presents the result of research on embryonic development of starry flounder Platichthys stellatus by means of artificial propagation and incubation in lightly aerated seawater. Fertilized eggs of starry flounder were isolated and spherical, contained no oil globules, and were buoyant in sea water. The egg membrane was thin, smooth, transparent and elastic. The mean size of eggs was 0.66-0.70 mm in diameter before absorbing water and 0.91 - 1.06 mm after fertilization and water absorption. According to the appearance and characteristics of the embryo, embryonic development was divided into 11 consecutive periods, cleavage stage, blastula stage, gastrulae stage, neurula stage, blastopore closed, formation of optic vesicle and somite, tail-bud forming, formation of crystal, formation of otocyst, pre-hatching stage, hatching stage. In 11-0.5℃ sea water, larvae hatched at about 101 h after fertilization. The total length of the post-hatch larvae was 2.3-2.5 mm. The long diameter of yolk sac was 1. 075-1.25mm and short diameter was 0.60-0. 675 mm.