The Tremadocian is the first stage of the Ordovician System and is subdivided into two parts in general. The Upper Trema......

记述了产于湘西泸溪特马豆克期锅塘组的刺尾虫类三叶虫Ｄｉｃｈｅｌｅｐｙｇｅ ｌａｔａ的个体发育过程。其最显著的变化有头鞍形状和比例的改变，头鞍沟、颈沟与背......

对皖南和赣北早奥陶世早特马道克期的Staurograptus重新研究表明,该属具有原始枝末端正分推迟、分支级数缩减和笔石枝密度降低的演......