【摘要】 <正> 本文描述的标本系黑龙江省地质局第一地质队在鸡西市龙山屯(图1)麻山群地层中采得。后生动物化石在我国东北北部地槽区系首次发现。这类无骨骼的软躯体多细胞动物化石,对于研究晚前寒式纪地层的划分、对比以及生命起源、演化十分重要。迄今为止晚前寒武纪的后生动物在世界上最具有代表性的应属澳大利亚的埃迪卡拉动物群(Ediacara Fauna),因该类动物在生物演化上尚属无壳的软躯体阶段,不易保存成为化石,多数以印模出现。迄今发现更多还原

【Abstract】 The metazoa fossils described in this short paper were collected by theFirst Geological Team, Geological Bureau of the Heilongjiang Province, fromthe Shichang Member, Liumao Formation of the Mashan Group. It is notice-able that the specimens were found for the first time in the geosynclinalfold belts of northeastern China. In this paper 4 genera and 6 species are described, of which 2 generaand 5 species are recognized as new. They are: Arumberia banksi Glaessnerand Walter, Jixiella capistratus (gen. et sp. nov.), Glaessnerina sp., Mashanialongshanensis (gen. et sp. nov.), M. angusta (gen. et sp. nov.) M. deformata(gen. et sp. nov.) , and M. annulata (gen. et sp. nov.). The description ofthe new genera is given as follows:Jixiella (gen. nov.) Type species: Jixiella capistratus Liu (gen. et sp. nov.) Diagnosis: Simple body, conical to cylindrical in shape, with smoothouter mantle; original flexible tissue disappeared. Parallel flat ribs dividedby shallow grooves developed under the smooth mantle. Distal margin indis- tinct. A concave depression set at the point of the concentric ribs. Remarks: This new genus has some features in common with Arumberia,especially the fossil form and the ribs and the shallow grooves. However, itcould be easily distinguished by the presence of the smooth mantle withoutflexible tissue of the ribs and the body is smaller than Arumberia. Mashania (gen. nov.) Type species: Mashania longshanensis Liu (gen. et sp. nov.) Diagnosis: Outline ellipsoid, often varying in form. Bilaterally symme-trical primary branches make an acute angle with the axis and contactwith the axis in a zigzag, sometimes the primary branches bifurcate in placeand may incorporate finer branches. Radiating primary branches developedin anterior. Posterior margin indistinct. Remarks:this genus closely resembles Pteridinium which is an impor-tant member of the Ediacara fauna, but differs from the latter in the pre-sence of radiate primary branches in anterior and the free body could be seenin different shape modified by bending or warping. The metazoan asemblage above mentioned is called by the writer theMashan Fauna. Considering the systematic position and its character, itseems that Mashan Fauna is closely related with Ediacara Fauna, but is pro-bably more progressive in evolution than the latter. The metazoa-bearing stra-ta of the Mashan Group may accordingly be referable to the Late-Pre--Cam-brian, and is approximatelly equivalent to the Xiadong Group of Siniansystem in south China, Vendian in U. S. S. R., and Wilpene group of Adelai-dean in Australia.更多还原