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以宽川铺生物群中获取的磷酸盐化立体保存的胚胎化石为研究材料,对胚胎化石表面超微结构和内部解剖结构进行观察并对比分析.结果显示,大部分胚胎化石表面被一单层光滑卵膜结构所包裹,卵膜之下胚胎形态多样;刺状结构位于卵膜之下,为原生质胚胎分泌而成的保护层,出现在不同大小和不同类型的胚胎中.结果表明:1)单一依靠胚胎大小或者表面结构不能作为胚胎的分类依据;2)与现生海葵等动物胚胎表面微绒毛相似,Olivooides表面刺状结构可能具有保护胚胎和生态扩散的功能;3)带刺Olivooides很可能发育成为动物演化早期最简单的带刺幼虫形式,是动物间接发育的证据.“,”Embryos are preserved in 3D as phosphatized permineralizations with superficial structures,and interior anatomy revealed in partly decayed embryos.Different species share a similar naked egg membrane and stellate cuticle which indicate that:1) It is improper to judge affinity by size or superficial structure of embryos;2) It is postulated that the stellate cuticle would provide physical protection and dispersal to suitable habitat.Such properties were also observed in extant sea anemone embryos;3) The stellate Olivooides may grow into a primitive larva,which could be the evidence of indirect development.