四川龙门山下泥盆统甘溪组和谢家湾组疑源类

四川龙门山下泥盆统甘溪组和谢家湾组疑源类的研究结果为首次报道。该两组疑源类丰富，分异度较高，共发现２３属、３３种和变种（包括未定种），文中图示１６属、２５种和变种。疑源类和其它孢型化石证明四川龙门山地区下泥盆统甘溪组和谢家湾组属近岸正常浅海环境的沉积。该地区甘溪组和谢家湾组疑源类基本上可与西欧、北美早泥盆世西根阶和艾姆斯阶疑源类比较。对它的研究不仅有重要的地层和古生物学意义，而且对古地理、古生态和沉积环境的研究也有重要意义

ACRITARCHS FROM LOWER DEVONIAN GANXI AND XIEJIAWAN FORMATIONS IN LONGMENSHAN MOUNTAIN,SICHUAN

Profuse and well preserved assemblages of acritarchs (microphytoplankton incertae sedis)occur in the majority of samples from the Lower Devonian Ganxi and Xiejia wan formations,Longmenshan mountain,Sichuan Province.The acritarchs assemblages comprise 23 genera,33 species and variaties. The acritarchs assemblages indicate a nearshore,normal marine environment, which is consistent with the interpretation provided by the associated shelly fauna and spores.Comparisons with other Siegenian and Emsian acritarchs assemblages indicate similarity mostly in terms of long ranges and cosmopolitan acritarchs species. The paper concludes with documentation and discussion of the stratigraphic occurrence of the acritarchs species.The age of the sediments is implied by other present fossil groups,and some of the restrictedly ranged acritarchs species are potentially useful for stratigraphic correlation. The Lower Devonian acritarchs undoubtedly have played a role in stratigraphical subdivision and correlation,as well as reconstructions of palaeogeography,palaeoecology and palaeoclimates.