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贵州瓮安前寒武纪陡山沱组含磷沉积保存了大量精致的生物结构,它们多数为微型球状,代表海藻,疑源类和处于不同发育阶段的不同动物类型的胚胎.文中报道了其中与腔肠动物有亲缘关系的胚胎和幼虫.这些胚胎由早期卵裂胚胎和双层状原肠胚所组成.它们均属于等大、辐射全卵裂类型.原肠胚多数具较大的原肠腔,原肠腔内充满了由卵黄递降所形成的有机残余.通过透射光学显微镜观察所发现的卵形或纺锤形浮浪幼虫状构造大多缺乏口,肠胃腔为卵黄递降物所充满.它们很可能代表非取食性的幼虫.只有少数浮浪幼虫具中空的肠胃腔和位于狭窄一端的口.将这些化石解释为取食性的幼虫.以上与腔肠动物可能具亲缘关系胚胎的研究将为动物起源提供一个新的视角.
Phosphorus sediments deposited in Precambrian Doushantuo Formation, Weng’an, Guizhou Province, China, contain a large amount of delicate biological structures, most of which are microspherical and represent the embryos of seaweeds, suspected sources and different animal types in different developmental stages. The coelenterates and larvae are related to coelenterate animals.These embryos are composed of early cleavage embryos and double-layer gastrulation.They are all of the same type, Intestinal cavity, the original intestine cavity filled with organic residues formed by the egg yolk descending by transmission light microscopy found oval or spindle-shaped larvae larvae most of the lack of construction of the mouth, gastrointestinal cavity filled with yolk descent. They are Probably representing non-feeding larvae. Only a few floating larvae have a hollow gut cavity and a mouth at the narrow end. Interpreting these fossils as feeding larvae The above studies on potentially related coelenterate embryos will be The origin of animals provides a new perspective.