ABSTRACT

Well-preserved holdfasts and early growth stages of the tubular cnidarian Sphenothallus are described from the early Silurian (Llandovery Series) of Washington Land, North Greenland. The diameter of the holdfast is determined by the formation of a basal disc attached to the substrate, upon which the initially conical, but subsequently tubular shell is formed. The characteristic opposing longitudinal thickenings are developed at each angular margin as the initially circular tube acquires an elliptical form.

中文翻译：

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来自北格陵兰西部早期志留纪（劳伦蒂亚）的蝶体（刺胞动物）的固守

摘要

从北格陵兰岛华盛顿地的早期志留纪（Llandovery 系列）描述了管状刺胞动物蝶体的保存完好的固定物和早期生长阶段。固定器的直径由附着在基底上的基盘的形成决定，在基盘上形成最初的锥形，但随后形成管状外壳。当最初的圆形管获得椭圆形时，在每个角边缘都会形成特征性的相对纵向增厚。